If its any help I noticed that in a built game when I changed the ambience in the setup.ini and played the game again ALL of the dynamic entities were black in game.
So I dont know whats causing it or how to fix it but an educated guess suggests its probably something to do with the way FPSC lights dynamic entities, there was some discussion in one of my other posts about entity lighting.
Glad to hear you got it fixed though. FPSC is great but it does seem to be a little fragile and require re installation at the drop of a hat.
Its always disheartening to see 'uninstalled and reinstalled fpsc and it fixed it'. I mean its great that it fixes it but its such a pain, Im currently running two concurrent versions (swapping the folder names, fps creator1 and fps creator respectively, around as its technically the same install but with differently updated fpsc.exes and map editor.exes) just to try and prevent this kind of reinstall business, by always having a usable working version to just replace key bits like the editor and fpscgame exe when things go wrong.
Saved my ass earlier today as the main version I was working in kept building the game with a fault, so i moved the necessary files over to the v1.20.17 folder, built the game using that exe and it worked just fine.
Just goes to show how easily things can go wrong in fpsc behind the scenes and you dont even notice till you get that error that stops you dead.
smoke em if you got em