For a project on which I'm working, we would be ready to offer a bounty for the creation of a patch to node_import that enables file downloads to be imported along with other standard product (from a CSV file that would have only a couple of additional columns compared to the standard CSV files used to import products with node_import).

Please reply to this thread or send a message if you would be ready to contribute to Ubercart in this way.

Best regards,

Peter