These defaults are a usability feature that apply to many clients who will do the same RA disposition repetitively.
Some users may use many different Dispositions and the defaults can cause confusion.
Allow them to be configured as "blank"
On RA Head, leave the Original Order # field as gray until the user sets the Disposition/ Credit-Ship/Credit by fields.
Steps to reproduce:
Read more at http://www.xtuple.org/mantis/view.php?id=6092