Paul I have been struggling with this for years, you have got to expect this from one programme to another as each have their different ways of doing certain things. If I use Serif or Freehand and export drawings as PDF's or EPS you get the same problem when you import them to AI that is why the "Smart Objects" in the Design Suite is so handy as you can edit one in another programme and then save.

There has been many tries getting a format which is universal and at the moment PDF's are the best method. When I try to make an income from a drawing or design I do the rough work in XPro and then finish it off in AI saving me time and effort. I don't find that lines are a problem when exporting but I wish AI was the same as FH as you could cut and paste from Xara to FH.