Couldn't beat level 4 as well... When I drove the tank very close to the middle blocking square it allowed me (drawn the line) target to the other side, yet I have no clue how to get the projectile to the other side, it always bounced :( I still had fun though! Trying to correctly angle the projectile to hit gate opening, wall and tank behind it was tricky, I honestly gave up after few tries, but I believe it is doable. How to beat level 4, seriously?!?!?! :D
