In order to help us to assist you with the report design, please send the report as an attachment. As attachments can be made only to support tickets, you should be added as a licensed developer to your company account.
In the meantime take a look at our examples, especially the Invoice
report, where Master/Detail relation is realized using a Subreport item.
the Telerik team
Telerik Reporting Q1 2013 available for download with impressive new visualizations. Download today from your account.