stuck in chapter 3 or 4?

[steelth1]

yes there was a bug. that alcove was the place i was talking about but there was nothing there. i replayed from the last checkpoint and there it was. that disk you mentioned is the crystal. a ghost is holding it and he drops it when you kill him. let me ask you this, i just player a painkiller demo and got the same feeling as when i first played this game. should i give it another chance too?