To temporarily fix this bug, restart your game client.[left][/left]
I’ve encountered this bug a couple of times already.
When the train crashes into the building the frontwall just disappears and the backwall is still there.
You still can walk though the backwall, but you stop right before it for a moment and then get teleported right behind it. Same goes for the Windows in that building for some reason.
The game runs really bad when this bug is happening and it freezes every couple of seconds.
It seems to affect most of the players on the server as two friends of mine always had it too when I noticed the bug.
And the Objective container is buggy too
On terminal is a new bug too.
When you get too close to the wall in the building near the destroyable objective wall you can see through the floor/roof
And the healing stations aura stays on the ground again. Welcome back bug! 
Only fix is restart.