Welcome to all of you. I think Bug is a Beauty in her own right.
Have you considered seeing a holistic vet and/or acupuncture vet? My holistic acupuncture vet is absolutely amazing. You can read some very interesting case studies on his website
http://www.apvet.com/index.html
While none of them exactly match what you are describing with Bug, you will see that with herbs & acupuncture skin and hair condition can be changed (It saved my Bichon's life after a stroke that left him paralyzed!)
Here are 2 different sites to find an acupuncture vet:
http://www.ivas.org/member_search.cfm http://www.aava.org/pub/directory_links_public.html
This is a site to find a holistic vet:
http://www.ahvma.org/
Others on YT can tell you the amazing results they have had with acupuncture. My vet was originally trained and practiced as a traditional vet, so it is so wonderful that he can make the best assessment for how to proceed with a problem.