I have a big problem!
When I play my map I see in a area only a back thing with nothing in it. You almost think it is a sort of wall. But when you walk through it you see everything very strange!
Well it is a lighting problem for sure. Can you post a screenshot of the room in the 2d window? Is the room underground? It is not the trigger. Try making the ceiling structual and not detail.
make the walls, floor and ceilings structural as tltrude said,
detail makes the map compile faster bcus of the way it handles light, therefore it's not compiling the room with lights in bcus detail brushes don't always catch light sources and don't make shadows
hope this helps, prob not cos it's all foreign 2 me :-/
It sounds like a func vis leafgroup that is not targeted to another vis leafgroup . It is a vis problem maybe a vis cut along that line maybe you can use a hint brush to change the way the map is vised . When vis is done it creates volumes that do not contain structural brushes so if there was a hint brush in that area no cut whould be made there on that line .
It might be your wall lights. The bright part of a light entity should not shine on both sides of a wall. It's ok if it sticks into the wall, but not all the way through it.
