Screenshot update.

screenshots/README.md

@@ -3,10 +3,24 @@
 The complete gallery was refreshed after Phases 100–105 on 2026-11-06, including
 MIDI preferences/import, the sample editor, creative workflows and real installed
 VST3 insert chains.
-These are actual rendered application windows and menus on a 1440 × 960 virtual
-X11 screen, without mockups, compositing or image edits.
+The gallery captures are actual rendered application windows and menus on a
+1440 × 960 virtual X11 screen. The promotional `overview.png` is a designed
+composite of cropped, proportionally scaled captures with added headings; the
+other captures have no mockups, compositing or image edits.
 
-![Arrangement with named sections](overview.png)
+![xtc promotional overview: arrangement, piano roll, mixer and modular effects](overview.png)
+
+Regenerate the 2400 × 1800 promotional overview after refreshing the gallery:
+
+```sh
+python3 tools/create_promotional_overview.py
+```
+
+This optional image composition script requires Pillow, Fontconfig (`fc-match`)
+and DejaVu Sans. It uses `sequencer-loop.png`, `piano-roll-velocity.png`,
+`mixer-playing.png` and `track-inserts-vst3.png`; no application UI is fabricated.
+The full screenshot capture target replaces `overview.png` with a raw capture,
+so run the composition script afterwards to restore the promotional version.
 
 The temporary demonstration project starts from
 `examples/projects/modern-session.xtc`, adding Intro/Verse/Chorus/Outro markers,