Hi Paul,
No problem, the founders of Serlio Software all came from Rational Software where we worked on the Rational Rose and Rational XDE core funtionality teams, so we're very familiar with the UML. In fact, the creator of CaseComplete is also the orignal creator of Rational Rose.
CaseComplete was built to be a Use Case and Requirements gathering and authoring tool, not a full-blown UML modeling tool. This is by design - there are many UML modeling tools out there but many of them don't provide quality Use Case gathering and authoring support - this is where CaseComplete excels.
With that said, CaseComplete will not have the ERD and data modeling support you're looking for. You can certainly create custom shapes and draw ERD's within CaseComplete, but those shapes won't represent any underlying custom model elements. For that type of support, you'll probably have to turn to a full-blown UML modeling tool for rich ERD creation and data modeling.
Hope that helps, please follow up if you need additional information.
Regards,
Jeff
