I don't have a character that benefits from carrying skulls, and the silly things are kind of heavy, so I've been just leaving them. But it turns out I need one for a puzzle in the lower levels (Grimrock 1). So I've been searching back up through the levels, looking where the skulls are supposed to be, looking in piles of loot I've stashed in various places. At this point I've gone all the way back up to level 2, and still have not found even one lousy skull!

At this point I'm not sure whether to try tediously searching through every hallway, room, and alcove from level 2 on down, or whether to just start the game all over. Very annoying either way. I'm even getting suspicious that the skulls simply vanish or vaporize if left sitting.

Has anyone else had this problem?