The game was cool.
3 small points:
- The game could be improved by telling you what the tower are doing before the level start.
- the limited amount of undo can be annoying, especially as the game is in 3d, so sometime you miscalculate the distance.
- also, I would have love to see a level with only the tower introduce at the last level, so most of the difficulty of that level would be to make the longer path possible for the enemies.