This Cinema 4D script allow you to see how a c4d.CUSTOMGUI_INEXCLUDE_LIST and c4d.CUSTOMGUI_PROGRESSBAR gui works. And this will also show, you can change or set the process bar color and other ui colors too.
Quick Video on how it works: https://streamable.com/55e1q
How to Install: .....\C4D RXX\library\scripts