Hi Florian,
Just purchased MP3TAG via the AppStore; saw your reply regarding Export/Import Mac <-> Windows.
Just wondering if you have plans to implement Export/Import Mac <-> Mac ... would make easier to “backup” settings and actions should one need to reinstall the Mac version.
Cheers
Hi and welcome!
First of all, thanks for your support! It's much appreciated 
Exporting the settings and importing on another Mac (or the same) is possible via the defaults command in Terminal.app. To export the settings you'd use
defaults export app.mp3tag.Mp3tag ~/Desktop/Mp3tagSettings.plist
and to import you'd use
defaults import app.mp3tag.Mp3tag ~/Desktop/Mp3tagSettings.plist
defaults delete app.mp3tag.Mp3tag SecurityScopedBookmarks
The last command is necessary to remove data that is specific to the Mac you've exported from.
Please note, that Mp3tag's settings are also part of every Time Machine backup you're doing and are restored if you restore from a backup.
Hi Florian,
Appreciate the quick reply!
I'll give that a "go"; I assume I can edit the export .PLIST with Mac TextEdit? If not, what PLIST editor should I use?
Thanks!
PS: So far so good, been able to match up the UI to Windows UI. 
It's not intended to be edited externally so don't want to give any recommendation. TextEdit doesn't support plists, it's a file format with binary components to it.
Makes sense ...
It would be nice to have a "friendly" way to export/import custom Actions (etc.); for example, I recreated the Windows version of the "Case conversion", "CD-R', and "Standard"; would have uploaded them to the forum in case they would be of help to others since I've already done the work.
Yes, absolutely. This is already on my list for a later version. I also like the idea of being able to export and share action groups and categories.
Is this plist UTF-16 compatible?
If the settings are in PLIST, then we should be able to convert mta from Windows to mac.
It is best to create this export utility inside mp3tag windows in mac format, we can import in mac.
I have a huge list of actions in windows which is makes a big hurdle to move over to mac.
How soon are we planning to build this bridge?