Receipt Register Report: Add new Paramater

Hi,

For Rxi Report: Receipt Register, I have a requirement to add a New Parameter( Receipt Class method).

After looking in some of the Discussions &  Rxi Reports Administration Guide  i found that, we can Add/Remove some fields/attributes using Reports Xchange Designer responsibility or to change the Output format to CSV/TAB/HTML.

I'm a newbie to Receivables. Can some one please confirm, if adding a new Parameter to Rxi Report is even possible?

Thanks

Vamsani