I had a very odd thing happen when upgrading our own system from Sage 100 2014 to Sage 100 2016. The only add-ins we have are JobOps and GetX. None of our panels are customized. After the upgrade the Customer Maintenance and Inquiry panels had large fonts and didn't look right. All of the other panels seemed to be OK. After a little investigative work I discovered that there were no definitions for this panel in Customizer. No definition AT ALL! Furthermore, since this panel did not exist in Customizer, I could not use Customizer to fix the problem! What I ended up doing is exporting just this panel from another installation and then copy that file and import it into our install. That fixed the problem.
My question is this, has anyone ever seen an upgrade where Customizer loses a panel definition?