Okay - I have fixed it.
You will need to manually edit your save file, first extracting the contents of the packaged file using the EE Pak Extractor, making edits, then repackaging your changes.
Follow this guide to editing save files:
http://larian.com/forums/ubbthreads.php?ubb=showflat&Number=605573&an=
The lines you want to change in this case are indeed the OwnerCharacter lines - the OwnerCharacter should be 0 - not the ID of your lead character.
