I am glad that you found us. I developed my methods and my ability YEARS ago, and only realized that there were communities for it about a year ago. I partly wish I had known about them earlier... but developing my ability to lucid dream was fun, because I had no name for it, and I thought I was inventing something new... Not that I was the only person that could do it. I just didn't know anybody else that could.
Anyway.. I wish I could personally help you, but I'm at my adoptee quota, and you sound like you've probably tried all of the basic methods.

Tell me... How much time do you devote to lucid dreaming, when you try it. How much sleep do you have, total, that night?

-sloth