When I view the level in preview mode, I do get a red wireframe around my level architecture (and blue around the models). When I look at it in build mode, I get a red wireframe around the entities that do show up (but most of my level isn't showing). Oddly, I cannot seem to move around in either mode, though previously in 6.4 (I'm in 6.5 now) I could at least move/fly-through in preview mode.