In one match I had a very unusual collision problem. I had grabbed a mech, shadowcat I think, and was walking out of the hangar. Smack. Right into an invisible wall. Backed up, got up to 70kph, hit it again. Tried going at angle, reverse, etc. Finally ejected through the building, landed on the roof, hopped down and grabbed my mech. Seemed to work fine after. Not sure if its related, but I was having a fall through issue as BA, falling through the stairwells in the base.