I’m not sure what’s going on with this surface, but there’s something up with the colour. It was created in a script using the OffsetSurface method. Not sure if that matters.
Notice how I can’t change the colour of the surface until I extrude it.
Maybe, but not as it currently stands. I thought about this a little more, and there’s one more big piece of the puzzle that needs to be mentioned. This surface was originally a closed polysurface with coloured faces. I copied it, exploded it, and it seems the colour assignment is permanently “baked” in even as a surface.* At this point, the RemovePerFaceColors won’t work as its just a surface now.
*But… if I just use the OffsetSrf command this issue disappears. It’s the OffsetSurface scripting method that seems to be behaving differently regarding the colour assignment.
I see this issue still exists. Mitch’s solution works, but this probably should get fine-tuned (I’m using the very latest RC and it’s still misbehaving).