Is the critical flaw that you're unable to move the bus after crashing into a wall? Because I can't move the bus after crashing into a wall.
Viewing post in City bus, Stealing for the Adult Boredom Charity comments
Part of the problem before was entirely phasing though walls, or being thrown into absolute nothing depending on the quality of your CPU...
Came about because it was stable in debug, wasn't until last minute testing in release I noticed how entirely broken movement was, so had to do emergency patch fix.