If your saying the bug is the explosions of the trees after ricocheting off the tank with HVAP, I think your taking things a bit too literal with a video game. After all shouldn't there be more sparks with a bunch of rounds bouncing of the side of a tank or plane? Shouldn't more parts fall off as they are hit? Shouldn't fluids trial off planes as they leak?
Life is realistic, video games not so much. As for the hits, again due to the angle of his tank to you, and having his turret pointed strait at you I see no problems with the ricochets you were getting, but I guess it's up to HTC to decide if there is a bug or not. From the looks of things, I don't think so.