I was constructing the scene in the "torus and sphere" composition I uploaded to the gallery, and at some point I had the thought of using "make parametric points" with "copy 3d object", to make a ring of spheres that follow the same basic path of the torus. The idea being that there would be a ring of spheres inside of the torus.
I realized that since the "copy 3d object" outputs multiple objects, it can't hook to a window input alongside of single objects that have been hooked to a window. It would seem that the objects would meet to all be retrieved using "get item from list" and hooked up one by one, or that the other objects have to be detached, and only the "copy 3d object" can render.
The only other thing I could think of as a solution would be to use a "render scene to window" somehow for one of the groups of objects, but then they couldn't cull against one another so the scene would render wrong.