You import preferences via the Yate>Import Preferences... menu item. Select the file you want to import from and what item types to import.
Preferences can also be imported by dragging a preference file (.plist) to the main window's file list area. You can configure what item types are allowed to be imported in this manner in Preferences- File List - Dragged preference file import settings - Configure.
While importing, you also select to overwrite or add imported items when they already exist. This option only affects named items: Actions, File to tag templates, Rename templates, Search templates and Tag lists.
Yate automatically saves its preferences each time it starts. The number of auto backups retained is configurable in General Preferences. Via the Yate>Import Preferences from Backup... menu item you can choose a backup file to import from.
You can view a summary of the contents of a preference file via the Yate>Examine Preference Contents... menu item. The summary describes in any of the import/export types are contained in the file. For compound named items, a list of the items is included. You can also perform this function by dragging a Yate preference file to the main window's file list area while holding down the Shift key.
Note that Yate supports the user mapping of Custom fields to audio file components. The import/export of this information is controlled by the FLAC Mappings, ID3 Mappings and MPEG-4 Mappings selections. It is inherently dangerous to import modified values for these mappings while files are loaded.