Hi Lori,
Sorry to hear about your problems. I have just been told today that I have systemic (full body RSD). Always knew deep down that it was but it's really hard to actually hear it from a large group of Doctors as i'm sure you're aware.

I'm mostly stuck in bed right now like you due to pain. I underwent a PT Program 2 years ago for 3 weeks and they had me do lots of exercises that are useful for when in bed. You mentioned that you had 1lb weights, I had to fasten them around my ankles whilst laying and straighten my legs out as much as possible and repeat about 20 times (start off a few times, then build up). I was also told to do this laid on my belly, side etc.
It did help strengthen my muscles quite a lot. I am a lot weaker at the moment so am attending PT sessions to try and help with that.
For my upper body, I do a lot of stretching when possible. Like you however, I have a back condition (herniated discs from childhood) that make it extremely hard and painful to do so. I have weights that I use in my arms and try and stretch them up but it is hard to do so.
I'm sure others will have some suggestions. These are just a few things I have learnt at PT. I do hope you feel better soon.
Alison.