1) Anytime I'm in the tank the game because very jittery, also when I shoot mortars I don't see any green, explosion, etc.
2) Change weapons is really slow, maybe this is T2 but I just don't remember it being so slow.
Have you set up the video settings in game?
Yes, the no mortar smoke only happens in the tank, its very weird.... I don't have any other issues other than when in the tank.