One of the reasons why I like the ghost-spirit hypothesis is because it's the halfway point between "gross matter" and nothing at all. Spirit is like a nothingness that is too subtle to notice, yet it does something. An Infinite Consciousness might be able to imprint upon this nothingness a set of rules, release it, and watch what happens. As these creations become more complex, it might become harder to see what happens.
"What was God doing before creating the universe, and for how long was he doing that? Where was he living? Is there a place called heaven and is it in this universe or another one?"
I liked Dr Ebon Alexander's explanation (the neuroscientist who had the NDE experience), Dr. Ebon had experienced that God has created many universes, like grapes on a vine. I like that representation. If you were an Infinite Being, Creator of universes, wouldn't you create a heaven, a paradise for souls who love you and want to be with you? I think that God can manifest a heaven on earth, I think of legendary places like Shamballa and the book: Life and Teachings of the Masters of the Far East. It's very magical. Everlasting life is possible. As for time scales, I'm not sure how to estimate time beyond the space-time continuum.
"Do cockroaches, ants, bacteria have souls and ghosts? What of viruses and plants? I ask because I want to know whether they share in the sub-divisions of God's consciousness you mentioned since they are living things."
I've heard of the idea of a group soul where hives, ant hills, and other clusters of insects share a single soul; and that soul evolves over a long time, across many species and eventually incarnates as a human. But one must be careful about thinking about such things because you will have realizations that are troubling. I guess God wanted an adventure, and guess what! You're it. lol
"Please convey my sympathy and hope no serious injuries? For a ghost to shove her, firstly it must be wicked and so capable of thinking and it must be able to exert force, and to do this from Newton's second and third laws, ghosts must have Mass. And what has mass must be matter. What sort of matter could this be, dark matter?"
Apparently, she was able to made peace with this spirit until she eventually moved out. The way I understand it, a ghost can store energy in the energy eigenstates of a wave-function (created by the spirit). How much energy does it take to push someone off balance? 10 Newton-meters maybe? That energy can come from the victim, from cold spots, from batteries, from other sources. Just a passing thought, a ghost might be able to absorb a tiny amount of momentum from it's victim over a long time (a few hours maybe) and then give it back all at once. It's just an idea. Could dark matter be at play? I don't know. I had imagined a scenario where the grey aliens are dark matter lifeforms who are aware of us, but we're not aware of them. So they occasionally abduct us just to check us out, or perform bizarre science experiments on us. There are possibilities that are freakish that could actually be true. In fact, if they know about us, but we don't know about them (other than the crazies who say they've been abducted) that gives the grey aliens a significant advantage over us as play-things.