If you're having a problem with Geneforge 5 crashing sometimes when facing tougher enemies(I.E. Unbound, Drakons, Gazers, etc), you are probably playing on Torment Difficulty. In previous games this just affected Monster/Enemy To Hit% and Damage Levels, in 5 it's switched up to raise everyone's level(Except your's and your creations). Due to this, it
sometimes causes enemy Dexterity levels to overflow, which, when that enemy gets a turn, crashes the game. Just turn the difficulty down to Hard and it never happens(At least so far as I've gotten, Gazak Ur)