Did you perchance disabled the pathfinding in the properties ?
Here's my .capx, can you take a closer look? My game today went crazy, I didn't do anything. Gameover starts playing in the start of layout, I can't understand why. Yesterday everyting worked fine. And yeah, maybe you'll help me how to make tank shoot single shots? Because it's shoots as many times as you press.
https:// drive.google.com /file/d/0B3Iu4HpEXzMaYTNfeGs2X2RpSGM/view?usp=sharing