The VisiSpecs Word Add-in is no longer in my menus.

Sounds like it was disabled by Word.  Quick Steps to guide you are File > Options > Add-ins > Manage COM Add-ins > Make sure VisiWord is enabled.  Here is a Microsoft article discussing add-ins in more depth.

https://support.office.com/en-us/article/View-manage-and-install-add-ins-in-Office-programs-16278816-1948-4028-91e5-76dca5380f8d