Level select:
Hold Start + A + B at the title screen. Release the buttons when the desired level is displayed. Alternatively, hold A + Select at the title screen.

Level skip:
Hold Start and press A to jump to the next level. Note: This is only effective during the first sixteen levels.

255 lives:
Enter NYOPUGLE as a password.

Continue game play:
Hold A + B and press Select(5), Start before the game over screen appears to resume game play at the last level played with a score of zero.