BMDS Desktop crashes on launch with “bad marshal data” (Textual/Rich incompatibility on Python ≥3.12)

[ScottCoffin]

BMDS Desktop fails to start on Windows with Python 3.12–3.13 — the terminal goes blank or throws ValueError: bad marshal data (unknown type code) from textual/style.py.

Workaround

Use Python 3.11 or run:

pip install textual==1.0.0 rich==13.7.1

Environment:

Windows 10/11 · BMDS-UI 25.1 · Textual 2.1.2 · Rich 14.2.0

Suggested fix:

Pin compatible versions (textual<2.0, rich<14.0) or update BMDS-UI’s TUI to support new Textual API.