Walk up to a door you wish to pass and turn around so your back is to the door. Hold down your fire button and tap the joystick in the opposite direction to the door. Then push the joystick towards the door and release the fire button. (THIS IS TRICKY)
------------ 1 ------ 2 ------ 3 ----- 4 ------- 5 ------ 6 ----- 7 --
EASY: ---- "BACK" | "LOUP" | "CINE" | "GOOD" | "SPIZ" | "BIOS" | "HALL"
NORMAL: -- "PLAY" | "TOIT" | "ZAPP" | "LYNX" | "SCSI" | "GARY" | "PONT"
DIFFICULT: "CLOP" | "CARA" | "CALE" | "FONT" | "HASH" | "FIBO" | "TIPS"