The exact error message varies depending on where in the preamble I insert the line, but all of the error message talk about option clashes. I understand from reading this page <http://tex.loria.fr/ctan-doc/macros/latex/doc/html/usrguide/ node39.html#SECTION00071000000000000000> that there's no easy way to resolve this kind of clash.
it is easy, when you do not insert the urls with LyX, then Lyx does not write \uesepacjega{url} into the preamble and you can use any option.
Herbert
