Well today I accidently came across something that worked!!! I remember reading about it once or twice on this forum but never understood how it could work so I didn't try it. Today I accidently tipped her head to the outside of the circle when asking for the canter and she got the right lead as soon as I did that after a couple of times not getting it doing it the normal (english/dressage) way!!!!!! We went back to trot and walk and then tried the transition again, I tipped her head to the outside and she got it again! Yay yay yay yay!!
Now I can work on building her strength on that lead and then start working on softening her up and collecting it and hopefully once she has a lot more strength on that side she wont need such an exaggerated tipping of the head to get her to pick up the lead.