That's a huge puzzle, if you know what I mean. There are lots of pieces in there and my thoughts are really only concerning a small piece of it I'm sure. Anyway, here was my train of thought:
At first I started wondering at the cause of this whole eating problem. It sounds like it won't go away too easily even if you do supplement calories. The first thing I did was try to find some side effects to the nebulizer. There is plenty of info. out there, but I honestly didn't dig too deep there. (Maybe it's something you'll want to look into.)
The second thing I did was to find out what Lanzol does. Not surprisingly, it's a drug that reduces acid in the stomach to prevent things like burning of the esophagus. It seems to be a prescription strength "Tums" more or less. I wasn't sure if you were aware of this, but antacids actually create more "heartburn" or "acid reflux." They only treat the symptoms. (It's the same way that cough syrup and fever reducers don't make you better.) In adults, at least, if you have heartburn or something similar (acid reflux) you should take apple cider vinegar because it ADDS MORE acid to help you digest your food. Probiotics are basically the same idea. I've heard it said that anyone who has ever been on an antibiotic in their entire life has a shortage of intestinal flora. Therefore, we should be eating fermented foods such as saurkraut (I hate the stuff) or kefir (which is pretty good) or Kombucha (a type of green tea I believe?).
The only other piece of the puzzle I'll be able to offer a clue on is the fact that since she was adopted, there's probably a chance that the birth mother didn't nurse her when she was born and therefore she didn't get that "golden milk" or colostrum that a woman produces the first few days following birth which is supposed to be great for a baby's digestive tract. I'd probably go as far as to say that colostrum sets us on tract to be healthy in our digestive system for life.
If I were in your shoes, I'd take the time to talk to a nutritionist who knows about these "supposedly wacky" alternative treatments. I know that modern medicine seems to help quickly, which is why it's so attractive, but our "medicine" seems to only treat symptoms and never gets to the root of the problem. For a baby that young, I'd try to get her on the right track to being healthy and beware of setting her up for a lifetime of covering up symptoms. (Think of it in terms of, say, if you had acne, is it better to do pore cleansing treatments followed with nutrient-rich moisturizers or just put on a bunch of cover-up so no one can see the pimples?)
I wish I could help more. My heart goes out to you and your little one. Hopefully that slightly "off mainstream" thought process to that small piece of the puzzle will help you find a solution. All the best.