Hi Julian,
What I mean is there are 2 ways to import data. The standard NB_Store format which uses XML and the CSV method.
If you use the XML method then you don't have to do anything apart from clicking the export and import buttons in the back office. The part where you may have to do more is that the import does not know what "ID" is used by the exporting systems, therefore it uses the Product Ref to check for existing products and hence updates or creates new ones based on that. if you don;t use Product/Model Refs then the import has nothing to work with!!... Although I think it'll still work, it will only create new products. But it's best practise to have unique refs if your exporting and importing data.
As for the mapping XML settings in the BO, that's just for mapping the CSV fields to the standard XML format, you only need look at this if your using a CSV file to import.
Regards,
Dave.