I tried doing a search before I posted but couldn't find anything about this. I've completed all the puzzles but for some reason in the "Puzzles Window" it says for puzzle 16 "This milestone has not been completed." I know it's been completed. I put the sundial where it was supposed to go and I got the little ghosts and heard their story. I actually listened to their story three times and the puzzle still isn't being shown that it's completed.