SV_SetBrushModel: NULL
There is an error with one or more of the brush entities in you’re map.
Example: You may have the “function_rotating” entity with only the “origin” brush (look for something like this in you’re junk.txt file - Entity 0, Brush 1: origin brushes not allowed in world), or you may have placed the “area portal” texture on a door entity (this may produce an error like - Entity 2, Brush 0: areaportals only allowed in world) etc.
Make sure you have both the origin brush and the brush that you are rotating selected before you give it a function_rotating. The same goes for any other entity that requires the origin brush. Also, check that there are no textures on any of the entities that shouldn’t be there.
Quoted from MODSonline.com
I had this error a while ago. I removed a func_door_rotating, but forgot to select the origin brush. I removed the origin brush also - and the error was gone.
Oh, just found out, that Ifurita covered that issue on his tutorial about “Adding New Brushwork to Existing Entities”