Dear Anders, thank you!
From a few weeks of usage of LyX I find that the error messages I get from LyX is rather meaningless. It appears to my that LyX cuts away exactly the important parts. I would suggest you look at the LaTeX log,
That´s what I did now. I do add the relevant part of the log here, maybe someone could tell if everything is alright with it.
or try to export to LaTeX and compile to see what exactly happens in LaTeX.
This does not work, because I use XeTex, and I get error-messages from TexShop.
Best* Jess