Cheats:
Abort the game then you enter in Top 10 and enter one of the next cheat codes.
Then you start another game you can see that happend.

Code - Result 
Betty - 30 credits
SHITMODE - Unknown
BUBBLEBOBBLE - Unknown
UGGLY - Unknown
ADULT - Unknown
GOTO - Unknown

You can skip stage then press 'A' after that.