Just tried it again. I always use the downloadable when available. So.. The controls work, I can hold right click and move the turret, I can shoot, everything is fine on that part. What I mean by not being able to aim means that they pop from the shadows, and I have less than a second to react. I simple don't have time, they smash into the tank. Also, they seems to come from one direction only, so If I travel in a different direction I don't see them at all. Also, when I was out of the tank, I was attacked by them, they left me low on life, but I haven't even seen them. They're too fast and I can't guess where they come from. I read and understood the controls. The tank controls ok, it's just the zombies that are too difficult to deal with.