I cleared those two folders and just made my way through a quickmarch game of just NiGHts, so i would imagine it was probably the cache, though i cant say im willing to play a more involved game (marathon) with nacsm. RED has never caused issues. I have a top-notch system and cannot believe a traditional overload crash could occur, although in the past on larger games at marathon speed do take minutes to process turns after the medieval era, but it never crashes on vanilla and only rarely crashed in the past with NiGHTS, which is why i spoke up about it. The cache thing is good, but i think there might be some kind of bug with NACSM on how the AI CS's process their turns or something