The game is cool, however...
The targeting system needs to go. If you tell it to target stronger, tanks are targeted and men walk thru. If you choose weaker, then it has to kill ALL the men first, and by that time, the tanks are half way (or more) thru the field. Further/Closer doesn't seem to affect anything. They still shoot at the far tank and let the guy walk into the base.
As for the tower limit, scrap that too. It doesn't work; we're still able to buy towers after we hit the limit. But that's ok. How anyone can win with only 8 towers is beyond me, especially with the targeting system how it is. The only thing I can think of is that it slows the script down as more towers are added, which is true.
As for the freezing problem, people need to put some money into upgrading their computers. Mine is an ok computer, and it was running slow as I got toward the end and had many towers and enemies on screen. It never froze, but it did run slow and/or 'pause' a lot as I had lots of action going on, but I've got 1.73 GB RAM in mine. If your game is freezing, buy more memory. Or a new computer.
Other than these few things, I thought the game was great.