Very last minute...
I'm (hopefully) uploading my final submission now, with 7 minutes to go according to the main page... A py2exe'd version will follow.As I didn't have time to dig up an appropriate licence, and I doubt anyone would be mad enough to want to crib a beginner's code, I'm considering this software to be Public Domain. Maybe it'll come in handy for teaching people how not to code well ;)
Anyway, I'd just like to say, this has been a blast! Many thanks to Richard for running a great contest, and I'm looking forward to playing everyone's games! Good luck!