Help with Report Variables

I have been doing battle with the SBO Customer Receivables Aging Report. I am trying to add the fields "Customer Reference" and "Creation Date" to the Repetitive area of the report with no success. All of the existing fields are variables, and the on-line help says to contact SAP support (which would be me) for help with changing variables. Does anyne have a list of these variables, or know how to define them?

Many thanks,

Mike.