Invincibilty:
     At  any  point  in  the game make your cursor into a skull. After
that,  press  the  left-Shift  key  + the F9 key. Hit both at the same
time. You will still take damage, but when your energy goes down to 01
you  stop  getting hurt. Sometimes this toggles the characters voices.
Don't worry, just hit the F9 key to get the sounds back.