Hi. I don't know if you should be worried or not, but it seems the fact that she can talk perfectly as her imaginary friend might indicate that her dyspraxia is emotional in origin? I don't know anything about dyspraxia - maybe it is emotionally based, anyway.
I find it really fascinating that she has an imaginary friend who appears not to suffer from dyspraxia as she does. All sorts of psychology stuff could be investigated there!
Does she see a psychologist or counsellor?