This is resurrecting an older thread but a search turned up this page.
Earlier in this thread the 'cannot cast undefined to bool: (file 'maps/mp/mp_backlot_fx.gsc', line 12)' was mentioned and the solution of putting the 'extreme' and 'maps' folder with the mod works for the first game. But when the game is over the next map in the rotation crashes and tells me the gsc files in 'gametypes' must be in iwd files. Which I assume means the fast file.
This is for home testing with just a single player on a listen server and doesnt seem to happen if I manually rotate the map on the command line in a standard empty LAN server. I also dont recall it happening at other times when the game is run as a LAN server with a single player on another computer and maps are rotated. I dont run and test as a listen server very often but for now its my only option. I suppose I never played more than one map that way and never experienced the problem before.
Other than compiling the scripts I am sure I am missing something simple.