diff --git a/NOTICE b/NOTICE
index 3f4f4afa..a95eb76a 100644
--- a/NOTICE
+++ b/NOTICE
@@ -14,3 +14,7 @@ list (author, source, license) is in assets/ATTRIBUTION.md.
 
 Inter (assets/fonts/Inter-*.ttf) — SIL Open Font License 1.1. See assets/fonts/OFL-Inter.txt.
 Showcase photographs by Ansel Adams, Dorothea Lange and NASA (docs/images/) — public domain. See assets/ATTRIBUTION.md.
+
+BIZ UDMincho: Copyright 2022 The BIZ UDMincho Project Authors
+(https://github.com/googlefonts/morisawa-biz-ud-mincho). SIL Open Font License 1.1;
+see assets/fonts/OFL-BIZUDMincho.txt.
diff --git a/ROADMAP.md b/ROADMAP.md
index ec11897f..34ef427f 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -189,3 +189,13 @@ own chart-based calibration (M11.4). Adobe matrices are never used.
   Local roots and cleanup, 85k-photo grid and catalog performance, background compaction, failed-save errors, GPU
   export hardening, clippy 1.99. Added the honest *Where we stand* assessment and *Where we're going* priorities; added
   tracker rows for camera colour, camera coverage and render fidelity.
+
+## Japanese interface and text watermarks
+
+English/Japanese interface language is persisted in UI state. Core menus have Japanese
+translations; untranslated panels and dialogs retain English. BIZ UDMincho is bundled
+under OFL for Japanese glyph coverage without system fonts. Text watermarks now accept
+`vertical: true` in export JSON/presets and expose an orientation selector. Japanese
+characters stay upright in top-to-bottom columns, with newlines starting columns to the
+left. This is basic lettering, without tate-chu-yoko, ruby, kinsoku, or general vertical
+OpenType shaping. The same coverage renderer serves 8/16/32-bit exports.
diff --git a/apps/lightcraft/src/main.rs b/apps/lightcraft/src/main.rs
index b118af96..e835917f 100644
--- a/apps/lightcraft/src/main.rs
+++ b/apps/lightcraft/src/main.rs
@@ -85,7 +85,18 @@ fn load_prefs() -> Option<UiState> {
         return None;
     }
     let bytes = std::fs::read(config_dir()?.join("ui.json")).ok()?;
-    serde_json::from_slice::<UiState>(&bytes).ok().map(UiState::sanitized)
+    decode_saved_ui(&bytes)
+}
+
+fn decode_saved_ui(bytes: &[u8]) -> Option<UiState> {
+    let mut saved: serde_json::Value = serde_json::from_slice(bytes).ok()?;
+    if saved.get("language").is_none()
+        && let Some(language) = saved.pointer("/settings/language").cloned()
+        && let Some(object) = saved.as_object_mut()
+    {
+        object.insert("language".into(), language);
+    }
+    serde_json::from_value::<UiState>(saved).ok().map(UiState::sanitized)
 }
 
 fn save_prefs(app: &LightcraftApp) {
@@ -345,12 +356,12 @@ fn main() -> eframe::Result {
             let session = open_session(in_memory, library_dir, seed_demo && files.is_empty());
             let mut app = LightcraftApp::new(session, services());
             if cfg!(feature = "japanese-local") {
-                app.ui.settings.language = lightcraft_ui_egui::i18n::Language::Japanese;
+                app.ui.language = lightcraft_ui_egui::i18n::Language::Ja;
             }
             if let Some(ui) = prefs {
                 app.ui = ui;
             }
-            lightcraft_ui_egui::i18n::set_language(app.ui.settings.language);
+            lightcraft_ui_egui::i18n::set_language(app.ui.language);
             app.integrated_titlebar = cfg!(target_os = "macos");
             if let Some(port) = control_port {
                 let rx = control_server::start(port, cc.egui_ctx.clone());
@@ -372,3 +383,16 @@ fn main() -> eframe::Result {
         }),
     )
 }
+
+#[cfg(test)]
+mod preference_tests {
+    use super::decode_saved_ui;
+    use lightcraft_ui_egui::i18n::Language;
+    #[test]
+    fn language_migrates_and_upstream_choice_wins() {
+        assert_eq!(decode_saved_ui(br#"{"settings":{"language":"ja"}}"#).unwrap().language, Language::Ja);
+        assert_eq!(decode_saved_ui(br#"{"language":"en","settings":{"language":"ja"}}"#).unwrap().language, Language::En);
+        assert_eq!(decode_saved_ui(br#"{"language":"ja"}"#).unwrap().language, Language::Ja);
+        assert!(decode_saved_ui(b"not JSON").is_none());
+    }
+}
diff --git a/apps/lightcraft/src/native_menu.rs b/apps/lightcraft/src/native_menu.rs
index 82ff0df5..8af250a5 100644
--- a/apps/lightcraft/src/native_menu.rs
+++ b/apps/lightcraft/src/native_menu.rs
@@ -342,7 +342,7 @@ impl NativeMenu {
     /// Per frame: run chosen items, then sync labels / enabled / checked and the text-focus
     /// accelerators with the app state.
     pub fn update(&mut self, app: &mut LightcraftApp, ctx: &egui::Context) {
-        lightcraft_ui_egui::i18n::set_language(app.ui.settings.language);
+        lightcraft_ui_egui::i18n::set_language(app.ui.language);
         while let Ok(key) = self.rx.try_recv() {
             if key == QUIT {
                 ctx.send_viewport_cmd(egui::ViewportCommand::Close);
diff --git a/assets/ATTRIBUTION.md b/assets/ATTRIBUTION.md
index 29c3ee42..3d2133c5 100644
--- a/assets/ATTRIBUTION.md
+++ b/assets/ATTRIBUTION.md
@@ -9,6 +9,8 @@ covers a whole directory), or if a licence file referenced in the Licence column
 | Path | Asset | Creator | Source | Licence | Added | Modifications |
 |---|---|---|---|---|---|---|
 | `assets/fonts/Inter-*.ttf` (Regular, Medium, SemiBold) | Inter | Rasmus Andersson | https://github.com/rsms/inter | SIL Open Font License 1.1 (`assets/fonts/OFL-Inter.txt`) | 2026-09-30 | none |
+| `assets/fonts/BIZUDMincho-Regular.ttf` | BIZ UDMincho Regular | The BIZ UDMincho Project Authors (Morisawa Inc., design TypeBank Co., Ltd.) | https://github.com/google/fonts/tree/63833b7d10bb1f86a8f0b91cba2d3ae1f68d1aa3/ofl/bizudmincho | OFL-1.1 (`assets/fonts/OFL-BIZUDMincho.txt`) | 2026-10-05 | none |
+| `assets/fonts/OFL-BIZUDMincho.txt` | BIZ UDMincho licence | The BIZ UDMincho Project Authors | https://github.com/google/fonts/blob/63833b7d10bb1f86a8f0b91cba2d3ae1f68d1aa3/ofl/bizudmincho/OFL.txt | OFL-1.1 | 2026-10-05 | none |
 | `assets/app-icon/` (`lightcraft.svg` and the PNG/ICNS/ICO/SVG files derived from it) | LightCraft app icon (lynx) | LightCraft project owner (drawn in ArtCraft) | original work (vectorised from the owner's drawing; see `assets/app-icon/README.md`) | MIT OR Apache-2.0 (`assets/app-icon/LICENSE.txt`) | 2026-10-02 | vectorised to SVG; rendered to PNG/ICNS/ICO by `packaging/icons.sh` |
 | `crates/scenes/` (generated images) | Procedural demo photographs | LightCraft contributors | original work (generated at runtime, no source imagery) | MIT OR Apache-2.0 | 2026-09-30 | n/a |
 | `crates/ui-egui/src/icons.rs` | UI icons drawn as vector paths in code | LightCraft contributors | original work | MIT OR Apache-2.0 | 2026-09-30 | n/a |
diff --git a/assets/fonts/BIZUDMincho-Regular.ttf b/assets/fonts/BIZUDMincho-Regular.ttf
new file mode 100644
index 00000000..b5a3f4cc
Binary files /dev/null and b/assets/fonts/BIZUDMincho-Regular.ttf differ
diff --git a/assets/fonts/OFL-BIZUDMincho.txt b/assets/fonts/OFL-BIZUDMincho.txt
new file mode 100644
index 00000000..1664f9f6
--- /dev/null
+++ b/assets/fonts/OFL-BIZUDMincho.txt
@@ -0,0 +1,93 @@
+Copyright 2022 The BIZ UDMincho Project Authors (https://github.com/googlefonts/morisawa-biz-ud-mincho)
+
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+https://scripts.sil.org/OFL
+
+
+-----------------------------------------------------------
+SIL OPEN FONT LICENSE Version 1.1 - 26 February 2007
+-----------------------------------------------------------
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font creation
+efforts of academic and linguistic communities, and to provide a free and
+open framework in which fonts may be shared and improved in partnership
+with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded, 
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply
+to any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components as
+distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting -- in part or in whole -- any of the components of the
+Original Version, by changing formats or by porting the Font Software to a
+new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION & CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,
+in Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the corresponding
+Copyright Holder. This restriction only applies to the primary font name as
+presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created
+using the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.
diff --git a/crates/engine/src/export.rs b/crates/engine/src/export.rs
index 70f89a7a..6ad24fca 100644
--- a/crates/engine/src/export.rs
+++ b/crates/engine/src/export.rs
@@ -202,6 +202,8 @@ pub enum Anchor {
 #[serde(default, rename_all = "camelCase")]
 pub struct Watermark {
     pub text: String,
+    /// Basic Japanese vertical lettering: upright glyphs in columns from right to left.
+    pub vertical: bool,
     /// Text height as a fraction of the image's short edge.
     pub size: f32,
     /// 0..1.
@@ -226,6 +228,7 @@ impl Default for Watermark {
     fn default() -> Self {
         Self {
             text: String::new(),
+            vertical: false,
             size: 0.035,
             opacity: 0.7,
             anchor: Anchor::BottomRight,
@@ -241,6 +244,9 @@ impl Default for Watermark {
 
 /// Inter SemiBold (OFL, see assets/ATTRIBUTION.md).
 static WATERMARK_FONT: &[u8] = include_bytes!("../../../assets/fonts/Inter-SemiBold.ttf");
+/// BIZ UDMincho (OFL), Japanese fallback on both native and web.
+/// Bundled OFL Japanese font bytes, shared by watermarks and UI glyph fallback.
+pub static WATERMARK_JAPANESE_FONT: &[u8] = include_bytes!("../../../assets/fonts/BIZUDMincho-Regular.ttf");
 
 /// Draw `wm` onto `img` (straight alpha blending of the encoded values).
 pub fn draw_watermark(img: &mut Rgba8, wm: &Watermark) {
@@ -288,23 +294,67 @@ fn watermark_coverage(width: usize, height: usize, wm: &Watermark, mut blend_px:
         return;
     }
     let Ok(font) = FontRef::try_from_slice(WATERMARK_FONT) else { return };
+    let Ok(japanese) = FontRef::try_from_slice(WATERMARK_JAPANESE_FONT) else { return };
+    let fonts = [font, japanese];
     let short = width.min(height) as f32;
     let px = (wm.size.clamp(0.005, 0.5) * short).max(6.0);
-    let sf = font.as_scaled(PxScale::from(px));
-    // Lay out one line.
     let mut glyphs = Vec::new();
     let mut x = 0.0f32;
+    let mut y = 0.0f32;
+    let mut tw = 0.0f32;
     let mut prev = None;
-    for ch in text.chars() {
-        let id = sf.glyph_id(ch);
-        if let Some(p) = prev {
-            x += sf.kern(p, id);
+    let columns = text.split('\n').count();
+    let mut column = 0usize;
+    for original in text.chars() {
+        if original == '\n' {
+            if wm.vertical {
+                column = column.saturating_add(1);
+                tw = tw.max(y);
+                y = 0.0;
+            } else {
+                tw = tw.max(x);
+                x = 0.0;
+                y += px;
+            }
+            prev = None;
+            continue;
+        }
+        let vertical_form = match original {
+            '、' => '︑',
+            '。' => '︒',
+            '（' => '︵',
+            '）' => '︶',
+            '「' => '﹁',
+            '」' => '﹂',
+            '『' => '﹃',
+            '』' => '﹄',
+            '【' => '︻',
+            '】' => '︼',
+            '…' => '︙',
+            other => other,
+        };
+        let ch = if wm.vertical && fonts[1].glyph_id(vertical_form).0 != 0 { vertical_form } else { original };
+        let face = usize::from(fonts[0].glyph_id(ch).0 == 0);
+        let sf = fonts[face].as_scaled(PxScale::from(px));
+        let id = sf.glyph_id(ch);
+        if wm.vertical {
+            let left = columns.saturating_sub(column.saturating_add(1)) as f32 * px;
+            let pen = point(left + (px - sf.h_advance(id)) / 2.0, y + sf.ascent());
+            let rotation = matches!(original, 'ー' | '—' | '–').then_some((left + px / 2.0, y + px / 2.0));
+            glyphs.push((face, id.with_scale_and_position(px, pen), rotation));
+            y += px;
+        } else {
+            if let Some((previous_face, previous)) = prev
+                && previous_face == face
+            {
+                x += sf.kern(previous, id);
+            }
+            glyphs.push((face, id.with_scale_and_position(px, point(x, y + sf.ascent())), None));
+            x += sf.h_advance(id);
+            prev = Some((face, id));
         }
-        glyphs.push(id.with_scale_and_position(px, point(x, sf.ascent())));
-        x += sf.h_advance(id);
-        prev = Some(id);
     }
-    let (tw, th) = (x, sf.ascent() - sf.descent());
+    let (tw, th) = if wm.vertical { (columns as f32 * px, tw.max(y)) } else { (tw.max(x), y + px) };
     let inset = wm.inset.clamp(0.0, 0.4) * short;
     let (w, h) = (width as f32, height as f32);
     use Anchor::*;
@@ -328,10 +378,17 @@ fn watermark_coverage(width: usize, height: usize, wm: &Watermark, mut blend_px:
     let passes: &[(f32, [u8; 3], f32)] =
         if wm.shadow { &[((px * 0.05).max(1.0), [0, 0, 0], 0.45), (0.0, wm.color, 1.0)] } else { &[(0.0, wm.color, 1.0)] };
     for &(off, col, a) in passes {
-        for g in &glyphs {
-            if let Some(o) = font.outline_glyph(g.clone()) {
+        for (face, g, rotation) in &glyphs {
+            if let Some(o) = fonts.get(*face).and_then(|font| font.outline_glyph(g.clone())) {
                 let b = o.px_bounds();
-                o.draw(|gx, gy, cov| blend((ox + off + b.min.x) as i32 + gx as i32, (oy + off + b.min.y) as i32 + gy as i32, cov, col, a * alpha));
+                o.draw(|gx, gy, cov| {
+                    let (sx, sy) = (b.min.x + gx as f32, b.min.y + gy as f32);
+                    let (sx, sy) = match rotation {
+                        Some((cx, cy)) => (cx - (sy - cy), cy + (sx - cx)),
+                        None => (sx, sy),
+                    };
+                    blend((ox + off + sx) as i32, (oy + off + sy) as i32, cov, col, a * alpha);
+                });
             }
         }
     }
@@ -1227,6 +1284,44 @@ mod tests {
         assert!(ExportOptions::from_json(&serde_json::json!({"watermark": ""})).watermark.is_none());
     }
 
+    #[test]
+    fn japanese_watermarks_support_vertical_columns_and_legacy_defaults() {
+        use ab_glyph::Font;
+        let font = ab_glyph::FontRef::try_from_slice(WATERMARK_JAPANESE_FONT).unwrap();
+        for c in "日本語".chars() {
+            assert_ne!(font.glyph_id(c).0, 0);
+        }
+        let old = ExportOptions::from_json(&json!({"watermark": {"text": "日本語"}}));
+        assert!(!old.watermark.unwrap().vertical);
+        let options =
+            ExportOptions::from_json(&json!({"watermark": {"text": "日本語", "vertical": true, "size": 0.1, "shadow": false, "opacity": 1.0}}));
+        let wm = options.watermark.unwrap();
+        assert!(wm.vertical);
+        let round: Watermark = serde_json::from_value(serde_json::to_value(&wm).unwrap()).unwrap();
+        assert!(round.vertical);
+        let mut img = Rgba8::new(400, 300);
+        img.data.fill([0, 0, 0, 255]);
+        draw_watermark(&mut img, &wm);
+        let lit: Vec<_> = (0..300).flat_map(|y| (0..400).map(move |x| (x, y))).filter(|&(x, y)| img.get(x, y)[0] > 64).collect();
+        assert!(lit.len() > 100);
+        let w = lit.iter().map(|p| p.0).max().unwrap() - lit.iter().map(|p| p.0).min().unwrap();
+        let h = lit.iter().map(|p| p.1).max().unwrap() - lit.iter().map(|p| p.1).min().unwrap();
+        assert!(h > w * 2, "vertical Japanese must extend down the column");
+        let two = Watermark { text: "日\n本".into(), anchor: Anchor::TopLeft, inset: 0.0, ..wm };
+        img.data.fill([0, 0, 0, 255]);
+        draw_watermark(&mut img, &two);
+        for (text, dx) in [("本", 0), ("日", 30)] {
+            let mut single = Rgba8::new(400, 300);
+            single.data.fill([0, 0, 0, 255]);
+            draw_watermark(&mut single, &Watermark { text: text.into(), ..two.clone() });
+            for y in 0..30 {
+                for x in 0..30 {
+                    assert_eq!(img.get(x + dx, y), single.get(x, y), "newlines move columns left");
+                }
+            }
+        }
+    }
+
     #[test]
     fn graphic_watermark_is_placed_scaled_and_blended() {
         let dir = std::env::temp_dir().join(format!("lc-wm-logo-{}", std::process::id()));
diff --git a/crates/mcp/src/tools.rs b/crates/mcp/src/tools.rs
index 7e2e212b..e7c1da94 100644
--- a/crates/mcp/src/tools.rs
+++ b/crates/mcp/src/tools.rs
@@ -205,7 +205,7 @@ pub fn helper_tools(has_ui: bool) -> Vec<Value> {
                 "removeLocation": {"type": "boolean"},
                 "colorSpace": {"type": "string", "enum": ["srgb", "displayP3", "adobeRgb", "proPhoto", "rec2020"], "description": "Output colour space (default sRGB; AVIF is always sRGB). adobeRgb = Adobe RGB (1998) compatible; the embedded ICC profile is generated from the published primaries"},
                 "bitDepth": {"type": "integer", "enum": [8, 10, 16, 32], "description": "Bits per channel: PNG 8|16 (default 8), TIFF 8|16|32 (default 16; 32 = linear float with a linear profile), AVIF 8|10; JPEG/WebP are 8-bit"},
-                "watermark": {"description": "Text, or {text, size (fraction of short edge), opacity, anchor (topLeft|top|topRight|left|center|right|bottomLeft|bottom|bottomRight), inset, color [r,g,b], shadow}"}
+                "watermark": {"description": "Text, or {text, vertical (boolean; defaults to false), size (fraction of short edge), opacity, anchor (topLeft|top|topRight|left|center|right|bottomLeft|bottom|bottomRight), inset, color [r,g,b], shadow}"}
             }),
             &[],
         ),
diff --git a/crates/meta/src/datetime.rs b/crates/meta/src/datetime.rs
index ed77ee9e..271aa67d 100644
--- a/crates/meta/src/datetime.rs
+++ b/crates/meta/src/datetime.rs
@@ -71,7 +71,7 @@ impl DateTime {
         };
         let (h, m) = match rest.split_once(':') {
             Some((h, m)) => (num(h)?, num(m)?),
-            None if rest.len() == 4 => (num(&rest[..2])?, num(&rest[2..])?),
+            None if rest.len() == 4 => (num(rest.get(..2)?)?, num(rest.get(2..)?)?),
             None => (num(rest)?, 0),
         };
         if h > 18 || m > 59 {
@@ -180,6 +180,17 @@ mod tests {
         assert_eq!(DateTime::parse_offset("+99:00"), None);
     }
 
+    #[test]
+    fn unicode_offsets_are_rejected_without_panicking() {
+        for offset in ["+1€", "-1€", "+€1", "-€1"] {
+            assert_eq!(DateTime::parse_offset(offset), None);
+            let date = format!("2024-06-01T13:45:59{offset}");
+            let metadata = crate::Metadata { capture_time: DateTime::parse_iso("2024-06-01T13:45:59Z"), ..Default::default() };
+            let xmp = crate::write_xmp(&metadata, None).replace("2024-06-01T13:45:59+00:00", &date);
+            assert!(crate::parse_xmp(&xmp).unwrap().metadata.capture_time.is_none());
+        }
+    }
+
     #[test]
     fn iso_roundtrip() {
         for s in ["2024-06-01T13:45:59", "2024-06-01T13:45:59.250+02:00", "1999-12-31T23:59:00-05:30", "2024-02-29T00:00:00Z"] {
diff --git a/crates/ui-egui/locales/ja.json b/crates/ui-egui/locales/ja.json
index 6c626e8f..6878d37d 100644
--- a/crates/ui-egui/locales/ja.json
+++ b/crates/ui-egui/locales/ja.json
@@ -948,5 +948,64 @@
   "memory only": "メモリ上のみ",
   "none": "なし",
   "not available here": "ここでは利用できません",
-  "of the following rules:": "以下の条件に一致："
+  "of the following rules:": "以下の条件に一致：",
+  "Effect": "効果",
+  "Image": "画像",
+  "Layer": "レイヤー",
+  "Type": "書式",
+  "Save As…": "別名で保存…",
+  "Exit": "終了",
+  "New…": "新規…",
+  "New": "新規",
+  "Orientation": "組み方向",
+  "Layers": "レイヤー",
+  "Properties": "プロパティ",
+  "Brush Settings": "ブラシ設定",
+  "Options": "オプション",
+  "Fit on Screen": "画面に合わせる",
+  "Cut": "切り取り",
+  "Paste": "貼り付け",
+  "Deselect": "選択を解除",
+  "Export As…": "形式を指定して書き出し…",
+  "Search…": "検索…",
+  "Theme": "テーマ",
+  "Pages": "ページ",
+  "Preferences": "環境設定",
+  "Preferences…": "環境設定…",
+  "Interface language": "表示言語",
+  "Open…": "開く…",
+  "New blank PDF": "空白の PDF を作成",
+  "Create PDF from file…": "ファイルから PDF を作成…",
+  "Create PDF from images…": "画像から PDF を作成…",
+  "Create PDF from clipboard": "クリップボードから PDF を作成",
+  "Combine files…": "ファイルを結合…",
+  "Save as…": "別名で保存…",
+  "Close file": "ファイルを閉じる",
+  "Close all": "すべて閉じる",
+  "Revert": "保存済みの状態に戻す",
+  "Print…": "印刷…",
+  "Document properties…": "文書のプロパティ…",
+  "Find…": "検索…",
+  "Advanced search…": "高度な検索…",
+  "Copy pages": "ページをコピー",
+  "Cut pages": "ページを切り取り",
+  "Paste pages": "ページを貼り付け",
+  "Fit visible": "表示範囲に合わせる",
+  "Marquee zoom": "範囲指定ズーム",
+  "Take a snapshot": "スナップショットを作成",
+  "Full screen mode": "全画面表示",
+  "Read mode": "閲覧モード",
+  "Switch light / dark theme": "明るい／暗いテーマを切り替え",
+  "Comments panel": "コメントパネル",
+  "Form fields panel": "フォームフィールドパネル",
+  "Clear form": "フォームをクリア",
+  "Find tools and commands…": "ツールとコマンドを検索…",
+  "Actual size": "実際のサイズ",
+  "Zoom to page level": "ページ全体を表示",
+  "Fit to width": "幅に合わせる",
+  "Display theme": "表示テーマ",
+  "Side panels": "サイドパネル",
+  "Text direction": "文字の方向",
+  "Horizontal text": "横書き",
+  "Vertical text": "縦書き"
 }
diff --git a/crates/ui-egui/src/i18n.rs b/crates/ui-egui/src/i18n.rs
index 386e445b..92355c30 100644
--- a/crates/ui-egui/src/i18n.rs
+++ b/crates/ui-egui/src/i18n.rs
@@ -9,17 +9,37 @@ include!(concat!(env!("OUT_DIR"), "/ja-formats.rs"));
 pub enum Language {
     #[default]
     #[serde(rename = "en")]
-    English,
+    En,
     #[serde(rename = "ja")]
-    Japanese,
+    Ja,
+}
+
+impl Language {
+    pub const ALL: [Self; 2] = [Self::En, Self::Ja];
+    pub fn name(self) -> &'static str {
+        match self {
+            Self::En => "English",
+            Self::Ja => "日本語",
+        }
+    }
+    pub fn parse(code: &str) -> Option<Self> {
+        match code {
+            "en" => Some(Self::En),
+            "ja" => Some(Self::Ja),
+            _ => None,
+        }
+    }
+    pub fn tr(self, source: &str) -> &str {
+        if self == Self::Ja { japanese().get(source).map(String::as_str).unwrap_or(source) } else { source }
+    }
 }
 
 thread_local! {
-    static LANGUAGE: Cell<Language> = const { Cell::new(Language::English) };
+    static LANGUAGE: Cell<Language> = const { Cell::new(Language::En) };
 }
 
 pub fn default_language() -> Language {
-    if std::env::var("LIGHTCRAFT_LANGUAGE").as_deref() == Ok("ja") { Language::Japanese } else { Language::English }
+    if std::env::var("LIGHTCRAFT_LANGUAGE").as_deref() == Ok("ja") { Language::Ja } else { Language::En }
 }
 
 pub fn set_language(language: Language) {
@@ -27,7 +47,7 @@ pub fn set_language(language: Language) {
 }
 
 pub fn is_japanese() -> bool {
-    LANGUAGE.with(|value| value.get() == Language::Japanese)
+    LANGUAGE.with(|value| value.get() == Language::Ja)
 }
 
 fn japanese() -> &'static BTreeMap<String, String> {
@@ -60,34 +80,34 @@ mod tests {
 
     #[test]
     fn language_switches_and_unknown_text_survives() {
-        set_language(Language::Japanese);
+        set_language(Language::Ja);
         assert_eq!(tr("Exposure"), "露出");
         assert_eq!(tr("my-photo.jpg"), "my-photo.jpg");
         assert_eq!(tr("develop.set"), "develop.set");
         assert_eq!(crate::menubar::display_item_label("album.addPhotos", &serde_json::json!({"id": 1}), "Color"), "Color");
         assert_eq!(crate::menubar::display_item_label("app.export", &serde_json::json!({"preset": "Color"}), "Color"), "Color");
         assert_eq!(crate::menubar::display_item_label("view.photoGrid", &serde_json::Value::Null, "Color"), "カラー");
-        set_language(Language::English);
+        set_language(Language::En);
         assert_eq!(tr("Exposure"), "Exposure");
     }
 
     #[test]
     fn translated_formats_preserve_counts_and_remove_english_plural_suffixes() {
-        set_language(Language::Japanese);
+        set_language(Language::Ja);
         assert_eq!(tr_format!("{n} photo{}", "s", n = 12), "12枚");
         assert_eq!(tr_format!("Exported {ok} of {total} photo{}", "s", ok = 4, total = 12), "12枚中4枚を書き出しました");
-        set_language(Language::English);
+        set_language(Language::En);
         assert_eq!(tr_format!("{n} photo{}", "s", n = 12), "12 photos");
     }
 
     #[test]
     fn preferences_round_trip_and_old_settings_remain_readable() {
-        let old: crate::state::AppSettings = serde_json::from_str("{}").unwrap();
-        assert_eq!(old.language, Language::English);
-        let settings = crate::state::AppSettings { language: Language::Japanese, ..old };
+        let old: crate::state::UiState = serde_json::from_str("{}").unwrap();
+        assert_eq!(old.language, Language::En);
+        let settings = crate::state::UiState { language: Language::Ja, ..old };
         let saved = serde_json::to_string(&settings).unwrap();
-        let restored: crate::state::AppSettings = serde_json::from_str(&saved).unwrap();
-        assert_eq!(restored.language, Language::Japanese);
+        let restored: crate::state::UiState = serde_json::from_str(&saved).unwrap();
+        assert_eq!(restored.language, Language::Ja);
     }
 
     #[test]
@@ -95,7 +115,7 @@ mod tests {
         let ctx = egui::Context::default();
         crate::theme::install_fonts(&ctx);
         let mut app = crate::LightcraftApp::new(lightcraft_engine::Session::with_demo(), Default::default());
-        app.ui.settings.language = Language::Japanese;
+        app.ui.language = Language::Ja;
         app.ui.left_panel = true;
         let mut text = String::new();
         fn collect(shape: &egui::epaint::Shape, text: &mut String) {
@@ -136,7 +156,7 @@ mod tests {
         // Locale affects presentation only: command ids remain the same.
         let ids = |app: &crate::LightcraftApp| crate::menus::menu_entries(app).into_iter().map(|entry| entry.id).collect::<Vec<_>>();
         let japanese_ids = ids(&app);
-        set_language(Language::English);
+        set_language(Language::En);
         assert_eq!(japanese_ids, ids(&app));
     }
 }
diff --git a/crates/ui-egui/src/lib.rs b/crates/ui-egui/src/lib.rs
index ef159ef0..ae7050bc 100644
--- a/crates/ui-egui/src/lib.rs
+++ b/crates/ui-egui/src/lib.rs
@@ -439,7 +439,7 @@ impl LightcraftApp {
 
     /// Per-frame logic before layout (control channel, renders, shortcuts, drops).
     pub fn logic(&mut self, ctx: &egui::Context) {
-        i18n::set_language(self.ui.settings.language);
+        i18n::set_language(self.ui.language);
         let t0 = now_ms();
         self.logic_inner(ctx);
         self.perf.logic_ms = now_ms() - t0;
@@ -587,7 +587,7 @@ impl LightcraftApp {
 
     /// Lay out the whole window.
     pub fn ui(&mut self, ui: &mut egui::Ui) {
-        i18n::set_language(self.ui.settings.language);
+        i18n::set_language(self.ui.language);
         let ctx = ui.ctx().clone();
         if !self.fonts_ready {
             ctx.request_repaint();
diff --git a/crates/ui-egui/src/menubar.rs b/crates/ui-egui/src/menubar.rs
index 32c61618..0e02c857 100644
--- a/crates/ui-egui/src/menubar.rs
+++ b/crates/ui-egui/src/menubar.rs
@@ -259,6 +259,8 @@ pub fn checked(app: &LightcraftApp, id: &str) -> Option<bool> {
     let u = &app.ui;
     let panel = |p: RightPanel| Some(u.right == p);
     match id {
+        "app.language.english" => Some(u.language == crate::i18n::Language::En),
+        "app.language.japanese" => Some(u.language == crate::i18n::Language::Ja),
         "develop.autoSync" => Some(app.session.auto_sync),
         "view.photoCounts" => Some(u.show_counts),
         "view.secondWindow" => Some(u.second_window),
@@ -668,7 +670,7 @@ const TITLE_GAP: f32 = 24.0;
 /// Width of the in-window menu bar's titles.
 pub fn bar_width(ui: &egui::Ui) -> f32 {
     let t = crate::theme::Tokens::get(ui.ctx());
-    MENUS.iter().map(|m| ui.painter().layout_no_wrap(m.to_string(), t.font(13.0), t.text).size().x + TITLE_GAP).sum::<f32>()
+    MENUS.iter().map(|m| ui.painter().layout_no_wrap(crate::i18n::tr(m).to_string(), t.font(13.0), t.text).size().x + TITLE_GAP).sum::<f32>()
 }
 
 /// The in-window menu bar (hosts without a native one): one dropdown per menu, or a single
@@ -677,8 +679,10 @@ pub fn show_in_window(app: &mut LightcraftApp, ui: &mut egui::Ui, max_width: f32
     let t = crate::theme::Tokens::get(ui.ctx());
     let bar = menu_bar(app);
     let font = t.font(13.0);
-    let widths: Vec<f32> =
-        bar.iter().map(|(title, _)| ui.painter().layout_no_wrap(title.clone(), font.clone(), t.text).size().x + TITLE_GAP).collect();
+    let widths: Vec<f32> = bar
+        .iter()
+        .map(|(title, _)| ui.painter().layout_no_wrap(crate::i18n::tr(title).to_string(), font.clone(), t.text).size().x + TITLE_GAP)
+        .collect();
     let total: f32 = widths.iter().sum();
     let mut clicked: Option<(String, Value)> = None;
     let start = ui.cursor().left();
diff --git a/crates/ui-egui/src/menus.rs b/crates/ui-egui/src/menus.rs
index 36b05f2e..50abfed3 100644
--- a/crates/ui-egui/src/menus.rs
+++ b/crates/ui-egui/src/menus.rs
@@ -11,6 +11,8 @@ use crate::state::{BeforeAfter, Dialog, RightPanel, ViewMode, Zoom};
 pub type UiCommand = (&'static str, &'static str, Option<&'static str>, &'static str);
 
 pub const UI_COMMANDS: &[UiCommand] = &[
+    ("app.language.english", "English", None, "Edit>Language"),
+    ("app.language.japanese", "日本語", None, "Edit>Language"),
     ("view.photoGrid", "Photo Grid", None, "View"),
     ("view.squareGrid", "Square Grid", None, "View"),
     // G: Photo Grid ↔ Square Grid (from other views: the photo grid)
@@ -202,6 +204,10 @@ pub fn parse_rgb(v: &Value) -> Option<[u8; 3]> {
 
 /// Handle UI commands; `None` means "not a UI command — send it to the engine".
 pub fn run_ui_command(app: &mut LightcraftApp, id: &str, p: &Value) -> Option<Result<Value, String>> {
+    if matches!(id, "app.language.english" | "app.language.japanese") {
+        app.ui.language = if id == "app.language.japanese" { crate::i18n::Language::Ja } else { crate::i18n::Language::En };
+        return Some(Ok(json!(app.ui.language)));
+    }
     let ctx = egui::Context::default();
     let r: Result<Value, String> = match id {
         "view.photoGrid" => {
diff --git a/crates/ui-egui/src/panels/dialogs.rs b/crates/ui-egui/src/panels/dialogs.rs
index 2af0ca1d..ea1bfa13 100644
--- a/crates/ui-egui/src/panels/dialogs.rs
+++ b/crates/ui-egui/src/panels/dialogs.rs
@@ -551,8 +551,9 @@ pub fn show(app: &mut LightcraftApp, ctx: &egui::Context) {
                                 wm.image_width = (width / 100.0) as f32;
                             }
                         } else {
+                            choices(ui, app.ui.language.tr("Text direction"), "exportWmOrientation", &[(false, app.ui.language.tr("Horizontal text")), (true, app.ui.language.tr("Vertical text"))], &mut wm.vertical);
                             field(ui, "Text", |ui| {
-                                ui.add(egui::TextEdit::singleline(&mut wm.text).hint_text("© Your Name").desired_width(f32::INFINITY))
+                                ui.add(egui::TextEdit::multiline(&mut wm.text).desired_rows(2).hint_text("© Your Name").desired_width(f32::INFINITY))
                             });
                         }
                         choices(
diff --git a/crates/ui-egui/src/panels/settings.rs b/crates/ui-egui/src/panels/settings.rs
index a3067aad..a380090e 100644
--- a/crates/ui-egui/src/panels/settings.rs
+++ b/crates/ui-egui/src/panels/settings.rs
@@ -91,13 +91,8 @@ fn choices<V: PartialEq + Copy>(ui: &mut egui::Ui, id: &str, options: &[(V, &str
 
 fn general_tab(app: &mut LightcraftApp, ui: &mut egui::Ui, t: &Tokens) {
     row(ui, t, crate::i18n::tr("Language"), |ui| {
-        choices(
-            ui,
-            "settingsLanguage",
-            &[(crate::i18n::Language::Japanese, "日本語"), (crate::i18n::Language::English, "English")],
-            &mut app.ui.settings.language,
-        );
-        crate::i18n::set_language(app.ui.settings.language);
+        choices(ui, "settingsLanguage", &[(crate::i18n::Language::Ja, "日本語"), (crate::i18n::Language::En, "English")], &mut app.ui.language);
+        crate::i18n::set_language(app.ui.language);
     });
     heading(ui, t, crate::i18n::tr("Library"));
     let location = match &app.session.library {
diff --git a/crates/ui-egui/src/state.rs b/crates/ui-egui/src/state.rs
index 9da865fc..5300078c 100644
--- a/crates/ui-egui/src/state.rs
+++ b/crates/ui-egui/src/state.rs
@@ -131,8 +131,6 @@ impl InfoOverlay {
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 #[serde(default, rename_all = "camelCase")]
 pub struct AppSettings {
-    /// Display language, independent of catalog data and command ids.
-    pub language: crate::i18n::Language,
     /// Library opened at launch when no `--library` is given (empty = the default location).
     pub library_path: String,
     pub startup_view: StartupView,
@@ -157,7 +155,6 @@ pub struct AppSettings {
 impl Default for AppSettings {
     fn default() -> Self {
         AppSettings {
-            language: crate::i18n::default_language(),
             library_path: String::new(),
             startup_view: StartupView::Last,
             confirm_delete: false,
@@ -203,6 +200,8 @@ pub const MIN_PHOTO_WIDTH: f32 = 360.0;
 #[derive(Clone, Debug, Serialize, Deserialize)]
 #[serde(default, rename_all = "camelCase")]
 pub struct UiState {
+    #[serde(default = "crate::i18n::default_language")]
+    pub language: crate::i18n::Language,
     /// The Build Previews run last announced (its identity, finished?).
     #[serde(skip)]
     pub preview_build_seen: Option<(usize, bool)>,
@@ -511,6 +510,7 @@ pub enum Dialog {
 impl Default for UiState {
     fn default() -> Self {
         UiState {
+            language: crate::i18n::default_language(),
             preview_build_seen: None,
             unsaved_seen: false,
             luminance_map_restore: None,
diff --git a/docs/localization-ja.md b/docs/localization-ja.md
index 142ec5b8..a6ce630a 100644
--- a/docs/localization-ja.md
+++ b/docs/localization-ja.md
@@ -1,8 +1,9 @@
 # LightCraft 日本語版
 
-このローカル版は、LightCraftを基に日本語表示を追加したものです。
+開発元に追加された基本的な日本語表示（PR #110）を、編集・読み込み・書き出し画面へ広げています。
+言語設定は開発元と同じ `ui.json` の `language` を使います。以前のローカル版の `settings.language` も読み込みます。
 
-- 「設定 → 一般 → 言語」で日本語とEnglishを切り替えます。選択は次回起動にも引き継ぎます。
+- 「編集 → 言語」または「設定 → 一般 → 言語」で日本語とEnglishを切り替えます。選択は次回起動にも引き継ぎます。
 - メニュー、写真編集、マスク、切り抜き、設定、読み込み、書き出し、主な処理状況を翻訳しています。
 - 通常表示と太字の双方に、SIL OFLのBIZ UDPGothicを組み込みました。
 - 翻訳は表示層で行います。操作コマンドのID、写真のファイル名、入力したメタデータを変更しません。
diff --git a/docs/parity.md b/docs/parity.md
index 2572e186..c890c215 100644
--- a/docs/parity.md
+++ b/docs/parity.md
@@ -793,3 +793,11 @@ From `08-lightroom-classic-extras.md` (Classic-only features) and part 2 of `06-
 | KEYC-DEVELOP | Classic develop keys (V, ⌘U, ⇧⌘U, R, Q, K, M, ⇧M, ⇧W, ⇧J, ⇧Q…) | P2 | 🟡 | `cmd:develop.treatment`, `cmd:develop.reset`, `cmd:crop.reset` | V, ⇧⌘R, ⌥⌘R, W, J, Y, ⇧Y, \ match; R/K/M/⇧M differ; no Classic keymap layer |
 | KEYC-MODULE-OUTPUT | Book / slideshow / print / map / web keys | P2 | ⬜ | | modules not implemented |
 | KEYC-HELP | Classic help keys (⌘/, F1) | P2 | 🟡 | `cmd:app.shortcuts` | ⌘/ only |
+
+### Japanese text watermarks
+
+`app.export` watermark objects accept `vertical` (boolean, defaults to false). The export
+dialog offers Horizontal/Vertical and multiline text. Japanese glyphs fall back to bundled
+BIZ UDMincho. Vertical lettering uses upright em cells and right-to-left newline columns;
+Latin stays upright. Advanced Japanese composition remains open. Regression coverage:
+`export::tests::japanese_watermarks_support_vertical_columns_and_legacy_defaults`.
diff --git a/scripts/package-japanese-macos.py b/scripts/package-japanese-macos.py
index 0aead4c7..f3e50dd6 100644
--- a/scripts/package-japanese-macos.py
+++ b/scripts/package-japanese-macos.py
@@ -42,7 +42,7 @@ shutil.copy2(root / "target/release/lightcraft-cli", macos / "lightcraft-cli")
 shutil.copy2(root / "assets/app-icon/lightcraft.icns", resources / "LightCraft.icns")
 licenses = resources / "Licenses"
 licenses.mkdir()
-for source in ("LICENSE-MIT", "LICENSE-APACHE", "NOTICE", "assets/fonts/OFL-Inter.txt", "assets/fonts/OFL-BIZUDGothic.txt", "assets/app-icon/LICENSE.txt"):
+for source in ("LICENSE-MIT", "LICENSE-APACHE", "NOTICE", "assets/fonts/OFL-Inter.txt", "assets/fonts/OFL-BIZUDGothic.txt", "assets/fonts/OFL-BIZUDMincho.txt", "assets/app-icon/LICENSE.txt"):
     shutil.copy2(root / source, licenses / ("Icon-LICENSE.txt" if source == "assets/app-icon/LICENSE.txt" else pathlib.Path(source).name))
 shutil.copy2(root / "docs/localization-ja.md", resources / "日本語版について.md")
 subprocess.run(["codesign", "--force", "--sign", "-", "--timestamp=none", str(macos / "lightcraft-cli")], check=True)