This shoulda been sorted a long time ago, so i took it upon myself to fix the flagroom gate / grate / doors.
Pipes no longer catch in the grate model.
I fixed it by creating an invisible door brush with the same dimensions, in the same position as the grate model. The new invisible door is a child of the same object that controls the grate model so it all moves together and behaves as it should.
Attached is a zip file with the modified source .vmf file, the compiled bsp and the lua.
http://downloads.fat-suzy.com/maps/ff_openfire_fix.zip
I personally think this should be fixed or included in the map that ships with ff.
Squeek