Limited Level Select
These codes form a sort of limited level select:
SKIP TO STAGE 2: at title screen put cursor on game start, now press and hold R on controller 2. Press START on controller 1.
SKIP TO STAGE 3: at title screen put cursor on game start, now press and hold L on controller 2. Press START on controller 1.
GO TO SPECIAL BONUS MISSION: at title screen put cursor on game start, now press and hold L+R. Press START on controller 1.