Thanks for the info on Light Origin Target, srry. Actually, I spologize for this question because it wasn't necessary. I anticipated having a lighting problem from the beginning, so I asked this question. But it turns out the brushes are evenly lit when they rotate without any special parameters. I don't understand why, since part of the brushes are receiving no light at the beginning, but I'll sit with it.
I have a follow-up question. The func_rotating's are gears which spin when a door opens and closes, so I want them to spin in an opposite direction when the door closes as they would when it opens. Is this possible?