I mean, what makes her spiritual experience a thing to dismiss lightly, and yours real?

As I said, I don’t dismiss what you call channeling, I just don’t trust that particular lady. Simple as that.

I’ve been in the room during an exorcism, and I must say that the possessed person sure looked like she was channeling

I’m not surprised. I would dare to bet it’s the same phenomenon. “Shamanic possession” comes to my mind. But as I’ve said, I think that those entities are basically autonomous mental programs. Btw. being mental makes them pretty “non-physical” and in line with your descriptions.

All of our senses work differently in different states […] I’d like to see scientists devise scientific tools that work like our senses do when we’re dreaming

Senses work exactly the same in all states. It’s our awareness that changes, hence it would have to be recreated together with mind. Then again, if I look at neuroscience and AI research, it’s exactly what they are doing. Or at least they are going in that direction. The real problem, however, is first person consciousness (well, there is no other).

What is perceivable to us in one state is different from what is perceivable to us in another.

You can train yourself to see your dreams projected onto waking state. I mean you can see random dream creatures roaming your room and the like. Those states you talk about are not some clear-cut barriers.

You only see God when you’re asleep of hallucinating!” To which I say, maybe, but that doesn’t mean I’m not seeing God…

I would say it this way — you don’t see the whole picture because you are looking into mirror. But technically we are looking into mirror all the time. The question is who or what is looking at itself ;)