PTC Modeler Allocation Matrix - Several Row Item Roles

Hi, 

I was wondering if it is possible to create matrices in PTC Modeler with more than one row item role. In my case, I would like to show both Blocks and Block Properties as row item roles in an Allocation Matrix. (Block Properties are created for the matrix using a reference tag).

If possible, how must the rowItemRoles in the properties be specified?

I would appreciate any help. 

Thanks, 

David