I can't get through this door. I can't find any chests with keys on previous floors. An NPC on 3rd floor gave me a key to chests. I looked up the hints and cheats for big ben and all I find are the puzzle codes. The floor I am on is the first code: frost, but I can't get the door to open that will lead me to the 5th floor. Again, I can not find any locked chests on previous floors. Any help?