this game SUCKS. fix the lockups and it will be playable, but when I'm creating a bubble and it locks up, only to have it burst, it makes the game too hard.
you might want to set it to not deduct money until you click on the tower to upgrade instead of when you select. Also it's hard to tell when a tower is fully upgraded. You can put all 3 elements to max on one tower, so that eliminates any strategy other than placement in this game.
ok, I see a physics problem here that makes this game much more difficult. You can't for instance position a ball exactly on a square by putting two hills three squares apart. example: X.0.X The ball should rest perfectly in the 0 with two raised hills in the X's. But because of the physics engine, the ball never comes to rest. it just bobbles there forever. Definately a major flaw that kills any sort of precise positioning. Past that your left with clicking to make the ball keep moving no matter what, and that makes this game too twitchy and less like a puzzle game.
 "Bubbles 2"){kind=icon}
 "Cirplosion"){kind=icon}
 "Defend your Kingdom"){kind=icon}
 "Contour"){kind=icon}