In a MFD, Favorites are simply existing records which have had a 'flag' set within them to mark them as a 'Favorite'. They are not separate or additional records, and when the database is saved as a MFD file, the Favorite flags are included.
The 'Favorite' display is just a version of the main 'All' display that filters all the records so that only those flagged as Favorites are listed.
If you reinstall a MFD which contains records set as Favorites, the 'flags' that do this will be reinstated too.
If you 'Append' such a MFD to an existing MF database, the 'Favorite' screen will list a combination of the ones from the appended file along with any favorites that were in the records already loaded in the MF.
Regards
Ian