chiefwhosm: I was slightly more fortunate in that I only lost one member of the squad to those stairs but yes, seems to be a map bug.

Never noticed any other things like that in the game.

In the old demo version (they fixed it in the retail) in the store map with the kidnapped person in the underground lair you used to be able to use the boxes at the front window to climb onto the book case in the corner and make yourself completely immune to damage (but still be able to shoot people) also on that same map and area you could fall through the window and out into the blocked off street area, you could then actually wander round behind the shop front and look in through the vents into the playable area (and fall through them into the game world, usually resulting in being shot by an AI).