Continue code:
To continue on the same level after you run out of lives, wait until
the "Game over" screen goes away. Then, on the title screen, HOLD DOWN
A+B while pressing SELECT 5 times. Let go of A+B, and press start.

Level Select:
When you are at the Title screen, hold Start + A + B. Then, release
when the level you want is displayed.

More lives:
To get 255 lives, use this password. NYOPUGLE

Skip Levels:
In the beginning of the level you want to skip (right after the
opening theme music stops playing and the words on screen disappear),
press and hold the Start button and (while still holding Start) press
the A button and you will skip to the next level.