Aloha: no time to read this all but you have my sympathy!
Dd was a complete nightmare sleeper too. Nap? Whats a nap? When I realised she was getting worse at night rather than better (around 8 months) I decided that she was going to have one nap a day in her cot, no matter what. Every day, a couple of hours after she got up, I put her in her grobag in the cot (with a short, and in retrospect useless, sleep routine involving milk and a story). And blackout curtains and white noise and everything else I could think of. She would then scream hysterically for about 45 minutes. You could hear her at the end of the road with all our windows shut. She didn't seem to pause for breath. She was so cross. I went in every 10 minutes. Eventually, she would sleep for 20-30 minutes (snuffling and hiccuping). And then wake up screaming and cross. When I would get her up and feed her and take her out to calm her down. I didn't bother with any more naps in that day and just let her do her own thing at night as usual.
This is the important bit. After about a week, she gave up. Crying time down to less than 10 minutes, sleep for 45 minutes, wake up happy. Repeat 3 times a day.
So then we started cc at night. It took a while, mainly I think because she was genuinely hungry (cr*p eater as well). But we did get there.
As she has got older and shown herself to be incredibly stubborn, I've understood what her issue was!
I don't know if this helps any.
If not, have you considered Phenergan? Or earplugs?