I just saw this thread, as I was IN the hospital with gastroparesis when you wrote it.
I too have MS and gastroparesis. They are saying that the IVSM "may" have tripped off my initial pancreatitis, and gastritis and that led me to gastroparesis. I have known for some time that I have a slowed reaction to food, and suffer greatly from constipation.
The more I research, the more I find folks just like us, with MS AND gastro issues. I am scheduled to go for autonomic tests to see if my MS is affecting my autonomic system as well as my central systems.
Im amazed when I google MS and gastroparesis. I find so much! Like the diet from http://www.gicare.com/diets/Gastroparesis.aspx
I hope you are feeling better.