I think that the edema should be addressed before continuing on with Iodine supplementation(and salt-loading).
What are you taking to address the edema? And you state- no water pills. Have you used water pills in the past? Were you prescribed water pills? What is the cause of the edema?
If I were you I would eat lots of fresh produce(celery and cucumber is good for fluid retention), drink plenty of water and most importantly, get some exercise, whatever you can handle. Take a walk... get as mobile as possible, circulation is vital.
Iodine supplementation can definitely put the eliminative system through a workout.