Ugh, I'm giving up. This is a brilliant custom story with a lot of nice scares and great ideas for hallucinations and dreams! But I cannot put the final thing together.
I was in fact missing one piece because I had missed one door in that dungeon. But I already had put two pieces into the altar then. Could it be that that messes up the puzzle now? Because none of the colors works on none of the edges of the altar for me.
While searching for the last orb piece I came across one small bug and one problem:
When I ran back to the beginnng of the map, the sound of William asking for help was played again - but he shouldn't be screaming because I chose the traitor path, right?
When I used the lever that had to be greased one more time and then moved towards the former door-of-destiny-area, I dropped into the water monster halls again. The problem was: This time that teleport orb didn't work anymore and I had to reload a previous game.