Tower Defense (Help!)

Okay, here's the rub. I'm doing a Final project for my Comp. Programming class, and I have chosen to make a tower defense game. the only problem is, i am having minor difficulties doing it. I already have a conversation going at:
http://www.alice.org/community/showthread.php?t=8464
but i would like to reach out to other members. I am putting a slightly older version of this program here. If you think i might have a problem (code-wise, not psychological), post.

That project is now done. any replys will be considered awkward, redundant, and redundant