As it is, I have to export the layer as a PDF document, then open that PDF document in CorelDraw or Inkscape for modifications, then save it as a PDF document, then create a new vector layer in PL, then import that modified PDF document into the new PL vector layer, then delete the original PL vector layer. Whew!
It would be a whole lot easier to have PDF as an additional option to the TIF and PNG file formats for the external programs.