Data Returns in FM model but not report

I'm stuck troubleshooting an issue between an FM model and a report using the model. The model uses an XDC file for ReqPro as a data source to do a 'live' access to ReqPro. When I test the query subjects in the FM manager a list of requirements is returned and everything looks good. In an report using the model and the exact same query subject, no data is returned. Running the 'view tabular data' option in Report Builder with one data item in the query returns no data when several rows are expected. No errors are reported on the model when validated. Any suggestions on next steps?
Thanks in advance.
Derry