Please don't worry about the weight gain: the oil you'll be ingesting will go thru you, since the Epsom Salts will dilate the biliary ducts (and also are laxative).
Most people with liver problems have them at least partially because of NOT ENOUGH "good fats" in their diet.
I also have lost weight since I started flushing, and I actually eat more now, maybe differently, and have lost cravings for certain foods.
Don't put off flushing: you'll benefit greatly in many ways.
(Think of removing all kinds of toxins from your body, unburdening the immune system,etc).