Clicked at a nice-looking thumbnail. Looked at how the comments voted 0 points. Immediately knew who made this game.
This time I'll try to give a fair review without even playing the game. I'm certain thegames8 are predictable enough I can pull this off:
First thing: Your game idea is pretty good but has done often enough I have to file this under "nothing new or interesting". From that I subtract 1 star because your version has fewer options then the game you copied. Another point is lost because you obviously didn't care enough to playtest the game which lead to a couple of bugs that you didn't remove. Another star is taken away because of the extreme imbalance. Instead of playing the game with an interesting strategy some of the thing you can buy are noticeably better then others so you just upgrade the tower and spam that one unit. Another star is lost because of how repetitive the game is. After two or three levels it becomes increasingly boring especially because you don't have to think about something like strategy while playing. I'll remove another point because of the obnoxious ads that on some computers even crash the game.
Final score: -3 stars. Too bade zero is the minimum I can give you. I strongly suspect you either use bots to upvote your own games or pay NG to get frontpaged. Your games are shit copies of decent to awesome games and you deserve nothing of the money you make from them.