Can I import databases from previous MacFamilyTree versions into MacFamilyTree 11?

Yes, when you open an older MacFamilyTree database with MacFamilyTree 11, a migration dialog will ask you, if the databases should be migrated to MacFamilyTree 11. Just confirm this dialog to automatically convert a copy of the database into the new MacFamilyTree 11 file format. If not yet there, the database will then be moved into the MacFamilyTree 11 database folder. Databases older than MacFamilyTree 5 are stored as a GEDCOM file. You can import GEDCOM files via the file menu.