The Customers page

Your customers are managed through the Customers page.
Customers are these companies you expect RMAs and repairs from.

Like the other screens - except for New RMA and Settings - this screen has a top part with a sortable / searchable grid with data records (your Customers in this case) and a bottom part in which the details of the selected record is loaded. Clicking an item in the top grid will load it's details in the bottom part.

Restricted Agents and Customers (from their Customer page) have no access to this page.

You need to enter at least one customer in order to be able to create new RMAs. 

Customers have their own "customers page" where they can view, track, print and - if allowed - enter new RMAs.