Hi HOSTIS72,
You are definitely on the right track by working on the report with Visual Studio, can you clarify further what you mean when you say that: every time I try and add in the XML it fails. ?
What is the background of this report? Was it created by the Report Wizard in CRM, or is it an Out of Box report that you downloaded the .rdl for? Is your CRM environment a CRM Online organization?
Thanks,
Matt