This solution allowed me to get to a template with a shape element for the WBS Addin. But I do not see the WBS addin tab that provides access to the WBS Addin's functionality. An example of the functionality that I expected to find is shown at this web address:
https://ntrajkovski.com/2012/03/12/how-to-get-wbs-work-breakdown-structure-from-ms-project-2010-to-ms-visio-2010/
The author of that page shows how to import an mpp file into a WBS Modeler templated Visio document using the WBS Modeler tab. But I just have the tabs File, Home, Insert, Data, Process, Review, View. The add-in also does not appear in the list of Addins
under Options.
I do not think this solution works for x64 Visio 2013 apart from offering a shape.
I am using x64 Visio 2013 Professional and x64 Project 2013 Professional.