I have completed and collected all the tiles, but it says I have only collected 4 out of 5 treasure pieces??!! looked through but still can't see where the 5th one is. Any ideas?
Look at the treasures for it to point you to where the missing piece is.
On PC look in museum/treasures and click on the ice clown treasure, Jack in the Box.
Then click on the part you are missing and it will tell you where it is.
Notes where the treasure locations are, it shows that there are 2 parts in Ice Castle and 1 in each the other locations.
pixel_player59107906 if you did all the tiles, you simply forgot to pick up the treasure.