On Mac OS, it would help reduce user confusion if the Launch Center window would appear automatically when the user activates FileMaker Pro while it is already running and no windows are open.
It happens often that the user will close all FileMaker windows and consider FileMaker "closed," then later return to FMP in order to do further work, only to find that "nothing happens" when they click on the FMP icon in the Dock.
Users must be trained to click File > Open in order to open the Launch Center window. New users in particular seem to find this difficult to remember.
It would be consistent with other MacOS apps (Mail, Contacts, Safari, others) if something were to happen when the app is activated by clicking on its icon in the Dock. In the case of FMP, opening the Launch Center window seems like a natural, obvious behavior.