Scroll down past this paragraph if you just want to know what not to do...

So I'm working on my map.. having a good time and all that good stuff... I decide to make one of the rooms look like the floor above it crashed in on it since Valve was so nice to provide the lovely debris models... I already had a breakable surface glass window in the room and I wanted it to be broken (due to the supposed cave in from up above).. so I figured I could either try to figure out how to use input/outputs and a trigger_hurt or a flying rock or something to make the window look broken before the player even gets to the room... In a split second I decided ahhh screw it, I'll just put the broken glass surface on the window and call it good enough. Well, after that, whenever the PVS with the window in it was drawn, sure enough, HL2 would crash. Tried tons of the classic tricks... using the cordon boundaries to section off the level, use vis groups to turn stuff on and off during compiles... but it took me forever... and I finally just found it... it was that stupid window!!!! If I had just left it alone or just deleted the damn thing I could have saved myself at least 3-4 hours.... ARRRGHH..

So lesson learned, boys and girls:

Don't put glass/glasswindowbreak070b onto a func_breakable_surf As soon as your computer tries to draw it, it will crashed HL2. I tried it on two PCs (one is AMD and the other Intel) so I'm only assuming it's a software bug and not something weird with my PC(s).

Hmmm, I made a VMF to show just what I mean, but I don't see a way to upload it...

here, use this: http://www.digitalfrag.com/hl2dm/so_lame.zip