I just went through hell after my Macbook updated Traktor without consent wiping all my libraries and settings.
Here is the fix if anyone else gets this…
Users> Documents > Native Instruments > Traktor (version) had all of the folders for new installation but no backups, which were hidden.
Use Finder to search for - Collection, Settings and History (Traktor files) and copy those back into the root folder.
Ping. All sorted.