Extra options:
Press Up, Down, Left, Right at the title screen. "Continue",
"Fire", and "1-P" options will appear.
Level select:
Enable the "Extra options" code. Press Up, Down nine times, 1
at the extra options screen. The word "Round" and a number will
appear at the bottom of the screen. Press Left or Right to select a new
starting level, from 1 to 50. Press 1 to begin game play at the selected level.
