>>386800259
Try it without the occlusion area components first, you don't need them.
Try testing the occlusion culling in the editor in the occlusion visualization view. Perhaps the sphere isn't getting culled properly. You did mark the walls and other room geometry as "occluder static" right? I'm getting the feeling the sphere isn't actually being culled, it's just skipping rendering it on the GPU but it's still being submitted by the CPU. That's why it's still a bit laggy.