I remember having trouble with aligning the stones in the last puzzle. Either I totally misread the hints in that book, or the whole thing is just random
Thing is, I used the same approach when trying to align them as I did on the other occations earlier in the game, only with that 180 degrees twist. I always ended up with the very tedious job of searchiing through every combination, excluding only the obviously wrong ones. I also think I can remember that the correct combination always baffled me, considering the hints given.