I managed to get the game working without changing my username or adding a new user account. If you have admin privileges on Windows, you can just make the folder C:\Users\Kevin\Desktop\gmtk and install the game there. I'm guessing somewhere in the code (either the user code or in the packaged PyGame code) it's using an absolute path when it should be using a relative path. I see you're in the comments blaming PyGame for the issue, but I'd be hesitant to throw blame at a framework used by hundreds of games, including every Ren'Py game. I experimented a bit with trying to unpack the distribution archive, but I'm not terribly familiar with Python intermediary binaries, so I'm not making much progress. It probably is a fixable issue either way, though.
As for the game itself, it's an interesting idea. I like the idea that there's a counterbalance with placing more blocks making the game more difficult. I don't think the game is terribly balanced for it, though, and I the level design(s) could have been more interesting. It's an interesting game either way, though.