I would like to offer $50 for someone to put documentation on ubercart.org for getting the product feature: file downloads, working with paypal sandbox or paypal live payment standard. Instructions would start with a clean install and list all the pages to be visited, settings to set, permissions, conditional actions, etc. After following the documentation, another user would be able to start a new drupal install and do a test product where an anonymous customer could purchase a file, and get an email with a link to download it and have the file listed in their files tab in their profile.
This is my first offer of a bounty. Sorry if it is out of line. Thanks, Cathy Theys

In case you missed the tag, this documentation is for Ubercart 2.x.
Thanks!
THANK YOU CATHY for your super work and video docs on this, and THANK YOU xurizaemon for the insights.