Begin a new game and at the entrance door, type the code
 "120763-090665". Hold the "CTRL" key and click on "OK". Push "CTRL"
 and "0" et choose to not save the game. Open one of you old savegame
 from this point, you can use one of the next codes.
 
 Cheat codes:
 
 LOBBY
 DRUM
 HALL1
 TAPESTRY
 GARAGE
 CHASM
 DALI
 ATTIC
 CELLAR
 VRROOM
 JUNGLE
 
 After you type a Cheat Code push the "ENTER" key to validate and
 you'll be transported directly into an another area of the game...
 
 At the rat shooting gallery, if you hold CTRL as you shoot the target
 rats, your revolver will be converted into a machine gun. You can then
 hold down the fire button to let off a volley of shots. Be careful to
 watch your magazine however, because once you run out of ammo, you