I don't care for the "mass_property_calculate automatic" config.pro option because of its global reach. EVERYTHING gets its mass calculated, whether you need it or not. This is especially annoying for assemblies that have a bunch of parts in them that don't have their mass set. You get stuck entering a mass property value for every one before the calculation can complete. I prefer to add a statement to the bottom of the pro/program file that automatically updates the mass properties for that specific part/assembly every time it is regenerated. If you want all new parts you create to keep their mass up to date, add this line to the pro/program statement in your start parts. And for those who are wondering, yes, pro/e is smart enough to change this line in the pro/program file if you rename/duplicate/create from this model.
MASSPROP
PART <part name="> (or ASSEMBLY <assembly name=">)
END MASSPROP
For more information on how this works, see the pro/e help documentation. In WF5, it's located under "Functional Areas / Program / Editing a Design / Mass Properties and INTERACT Statements / Updating Mass Properties When Geometry Changes"
Tom U.