As a last resort you can disable the whole thing by going into:
World Settings: Lightmass: Force No Precomputed Lighting
And check it. No more precomputed lighting means no more attempts to attach to the swarm. No swarm, no cry. On the other hand, this will negatively impact your runtime framerate to some degree. How much? No idea… but it’ll be a hell of a lot better than “can’t build your game”.
I work on a relatively restricted network, on a game with nothing much going on with lighting, so this is an option for me. On the other hand, mucking about with my own registry (and FIPS in particular) isn’t an option. Your Mileage May Vary.