This games script is wrong

Greetings Kirupians!

Although it says my script contains no errors, theres something within this tetris code which is causing problems when loaded into my main Flash movie. My main movie has two buttons; each loads different games. The problem occurs if tetris is loaded more then once. The game goes…well, weird! Its best discribed if seen. I’ve attached the files on the off chance someone can take a peek. The error has to be within the games action script.

Any help - my god - would be appreciated at this stage as this problem has had me going round in circles for weeks!