Good game! Has a few glitches you might need to look into fixing though.
I also had to deal with sticky screen movement, but I don't think it's an issue with the game, I think it's a glitch between flash and the web browser.
But I did notice an interesting glitch on the town level. I built my path and it passed the top left corner of the map (the square at (3,0)). When the mobs ran the cource they froze at that spot.
It makes for a fun exploit for the player, but I don't think that's supposed to happen.