i'm not a newb mapper, i'm intermediate at least, but this problem has completely bewildered me. I compile my map, do all the stuff, blah blah. The only fence that's in there all of a sudden turns green!. It's a green fence. I look above it. The little bar i put as a top is also green on one side (the side that's facing same as fence) and bottom is blue.
So i open up the console to see if i can fix it. Only one error. Says that occlusion could not be found in it's material_occlusionproxy area. Only problem is, i don't remember putting an occlusion effects in my map.