I may have figured out why the SWF import brings in a lot of white objects. Xara seems to be exporting white objects and then tinting them at runtime. But on import something is lost. A solid-colored object will import to Flash as white. A linear-gradient object will come into Flash as a movieclip with an advanced color effect. This fixes the fill but not the outline.

Still no closer to a working solution. I really don't want to have to use Illustrator.