Medals are not working for me in the NG player.

Thought I had it all covered the first twelve waves, but suddenly it seems like some new kind of strategy's required... felt like the force fields were the secret, but suddenly they can't keep anything safe after all. Good game, though the strategy's a bit confusing, and construction a little buggy.

-cd-

I really like the game, but it has a ton of crippling glitches. Sometimes the guns just choose not to fire at all, and the mechanic walks outside of his area and directly into the enemies a ton.
These game breaking bugs are really what's holding it back for me, and if not for those I may have given it a 4 or 5.

its easy to place mining buildings and power building inside of eachother, just place it above an already placed building, and it will be fall and be placed in the same place as the already placed building.this can also push buildings off the left of the screen. but placing too much causes lag. also @scatmanfan101 , you lose when an enemy gets all the way to the left of the screen.

Its strange, I kept losing even though my little computer was perfectly fine. Is there a reason, or is it a bug?