Silkworm

Cheat mode:
Type scrap 28 at the options screen to enable cheat mode with unlimited lives.
Press [Keypad 0] to [Keypad 9] to select a level.
Press the function keys to slow the game down by different amounts.
Note: Cheat mode in early versions of the game is activated by pressing [Help] + Fire at the options screen.
If the message "Congratulations!, you have found the cheat mode...
unfortunately it has been ZZAPPED" appears, go to the control selection, press [F10], type scrap 28, then start game play.