Enhancement: the File URL should not require a base URL.

All the download File URLs want absolute URLs.

When preparing and testing a site using a test domain like "test.example.com", instead of the production domain "www.example.com", requires that all the download product File URLs be updated one by one when the site domain switches from testing to live domain.

Would be much simpler if MarketPress simply prefixed each File URL with the WordPress Site URL setting at runtime (vs doing it at time of the page update).