A2plus - when changing transparency of objects imported from STEP models, the color of the model is set to default (gray).

[karlitzky]

Problem description:
PCB design exported from Altium as a STEP model was imported into FreeCAD and lated used in the bigger assembly using A2plus workbench. While changing transparency on that PCB, all of its components lost their face colors (the whole PCB became uniformly default grey).
The original color is kept while in 'transparent state' but becomes gray when returning to 0 transparency.

Full version info
OS: Windows 11 build 22621
Word size of FreeCAD: 64-bit
Version: 0.21.1.33668 +26 (Git)
Build type: Release
Branch: (HEAD detached at 0.21.1)
Hash: f6708547a9bb3f71a4aaade12109f511a72c207c
Python 3.8.10, Qt 5.15.2, Coin 4.0.1, Vtk 8.2.0, OCC 7.6.3
Locale: Polish/Poland (pl_PL)
Installed mods:

• A2plus 0.4.60n
• InventorLoader 1.4.0
  Subproject(s) affected?