color_brightness (percent, default 100: unchanged) scales the models' vertex
colors, not the icons', for servers where the made models look brighter than
they should. transparent_colors names color ids drawn transparent whatever
Materials.xml says: 129 (Tr. Bright Bluish Violet with Glitter) has alpha
255 there, so it came out opaque; a named color gets transparent_opacity.
Both default to off, so models come out byte for byte as before.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>