I have extended an existing class from the Pega Marketing for Comms (PegaComm-Data-ProductHoldings).  When I look at the Data Model view in the Data Explorer (App Studio or Dev Studio) I can only see properties inherited from PegaComm- and nothing from ProductHoldings.  These properties bear no correlation to the exposed properties mapped through the Sources tab, and visible in the Records tab.  I know the later are defined by the DataTableEditorReport, but where is the metadata for the Reuesable Fields.

Also, if I add a property via the ‘Data object:’ landing page it appears in the list, but if I add it as a property rule it does not show up.  Where is the metadata for the list, and how can I modify the class to show more properties that were probably not added in the Data Explorer?