Yup, the game works fine now! This game reminds me of Plants vs Zombies. I think the game's good, but I do have a couple of suggestions:
Maybe add different ways to control the camera's movement? I think that being able to play this game entirely with the mouse could be good. So the scroll-wheel could be used to move the camera, or arrows at the right side of the screen or something like that.
I think that the pusher is a little overpowered for it's price. Maybe it could take a battery for every use instead of when it was built? Also the pusher could display the remaining uses in some way, like with a separate blue or red bar.
Lastly, I think that the rotating tower should target enemies that are the closest to them and not the base.
I also found a couple of bugs. The most glaring one is that the rotating tower doesn't aim at the center of the enemy, but at the bottom left corner. Also, if you demolish the tower and rebuild it, it stops aiming for some time. The red enemies don't spawn in any level past the one they were introduced in. Finally, in the settings menu the resolution selection moves way too slowly with the scroll wheel. Multiplying it's speed by 5 or so will make it much nicer.