I decided to download and try the map ( great map by the way :) ). And was trying out some nades when I discovered that i could throw through the garage door. Just a little minor detail i thought I would point out. Not that it matters because you can throw the flash just a few steps forward anyway.

Here is a photo of it

http://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=327753265