I keep on working on my project and decided to post some of the new stuff.
First is one of bonuses that player picks during the game. This one turns your tank into a robot that can ignore obstacles and have powerful rocket launchers hidden in his arms.
<img src="http://i34.tinypic.com/2zyzcdx.png">
And this robot is one of the 1st level enemies. I call him Megabomber =)
<img src="http://i34.tinypic.com/vfzi11.png">
<img src="http://i38.tinypic.com/1zefv54.png">