Orc saboteurs are making problems with all game, no matter what patch is it.
sdshadow have same problem with them, me also and i think other ppl have it too. So far no explanation from mod developers considering saboteurs
Try to kill them with aoe dmg spells, so far i figured out that any direct targeting spell (fire arrow, poison skull, blind, fear . . .) make game crash, but aoe spells hitting them work ok. So get some high initiative unit, and attack them that way and hope to kill all stack before they get their turn.