How can i use this module?

I'm on the same journey and will try to provide some basic docs here as I go:

1. Download, install, and enable the module under Ubercart Extra - UC Sell CCK Fields Access
2. Create your cck "product" nodes as usual (Ubercart > Manage Classes)
3. Append any cck fields to which you wish to sell access (under the usual CCK content Manage Fields)
   Note: Be sure this cck node type is an Ubercart product for the next step..
4. Protect the fields under Admin > Content > Content field privacy: /admin/content/uc_sell_cck
   This page lists all your Product classes and any CCK fields that can be protected.
5. Adjust the workflow/Conditional Actions to add Grant CCK field access to customer
6. Not sure what to do from here.. At this point, I can see that the order is complete, and when the user is authenticated, he can now see the CCK when viewing the product..... There's got to be a better way at this point, but this will get you up and running.

I wanted to sell links, so I protected the CCK Links field on a CCK node using this module.