This would be better with a 1024x1024 texture. With it being stretched the quailty is going down, and mainly we are only seeing the bump, and not the plaster it's self. I'll try it on a different preset next.
it cuts to pitch black.... you're walking around and the lighting changes suddenly? probably optimisation needed.
Looks like they have differing spotlight widths. Even though you say they are the same. Unlikely that the viewing angle would have such a large effect. Perception isn't that strong... is it?
Are those props meant to be prop statics? They may need to be dynamic. When viewing the model in the model viewer (duh) click the tab "info" and see which boxes are ticked. These are the type of prop they can be. Also, deleted props appear in the compile log, so check that for further details or post it here. Is your world saving new edits or loading an old BSP each time?