I’m have two static light behide a window with source radius 50 (like RealisticRendering demo). After baking i’m have reflection this lights on not rough materials. It’s start from 4.8 p1, at 4.7.6 all is fine.
Thank you for your patience as we looked into this issue for you. I talked with our rendering team and this circle you are seeing is actually intentional. It was added as a way to represent the source sphere light that was missing from static built reflections until 4.8. I can understand where this might be an issue and adding a stationary skylight with even a min. intensity should eliminate these spheres from your reflections.
The black sphere is actually because Spotlights only face one direction and when the sphere reflection capture actor is pulled to the rear of the spotlight the white reflection of the light source returns a zero value in a spotlight and renders as black. This is a known current limitation as spotlights should actually be rendered not as sphere lights from source but as disc lights.
There is currently no way to selectively remove static sources from reflection capture actors beyond changing the Source radius to adjust their size which can be done on a per light basis.