My daughter also has both RSD and gastroparesis. After struggling to keep the weight on for the past several years, TPN feedings have become necessary. They have also diagnosed her with immune system problems, and she is now receiving IVIG which has the potential to heal damaged nerves. Her GI specialist has seen some good results in treating gastroparesis with this treatment. It sounds to me as if your immune system may be involved as well. Isn't Crohns an autoimmune illness?