Ener the following code '?TJL BDFW BFGV JVVB' without the quotes then 'Start' the game. Press 'Pause' and go to 'Features' and ALL Levels, ALL Maps, ALL Weapons/Ammo, Max Health and Invincibility will be unlocked.
level 32 In the staging area, explode all barrels except the 1st one. Then go to teleporter to come back to begining. Explode the 1st barrel and hurry to the door behind you. If you're fast enough, you will be teleported to stage 32.(this is one of the most difficult stages in the entire game.)