To initially set up and save rating file for new library in Songbird.

Being new to Songbird, I wanted to switch my music ratings over from Windows Media Player and I found a way that works for me. Hope it works for you.

Create .m3u individual playlists for each rating in your existing music player. I named mine for the star rating they represented (5 Star, 4 Star, etc).
Search for the newly created file name(s) and verify folder location of saved playlists, Windows Media Player defaulted to my ripped music folder.
Open Songbird
Songbird File dropdown menu - Import Media, choose the music folders you want to add.
Songbird File dropdown menu - Import Playlists, import all your newly created (.m3u) ratings playlists. Songbird will keep the original playlist names with added ext (.m3u).
Songbird playlists – open first newly imported playlist, highlight first song.
Edit menu – Select All
Tools menu – Metadata Editor, select yes, add star rating for list, ok to close.
Repeat for each Songbird playlist to add ratings.
Now duplicates need to be removed.
Songbird Tools menu - Add-on, Exorcist
Activate Exorcist by restarting Songbird to Library tab
Songbird View menu - Media Views, Duplicate Tracks, Click on “Exorcise the Clones!” button at top to remove all duplicates (Songbird will favor rated music over non-rated music). Be patient, it will take a bit to complete.
Songbird Library Tab, Tools menu – Ex-/Import Ratings, choose rating file location.
Name ratings doc – Important: end name with .srf, Songbird does not automatically add extension.
Update rating list by Exporting ratings, don’t forget to add the .srf extension to the name each time you update the rating file.
Ratings have to imported each time you clean out our Library.
Songbird Library Tab, Tools menu – Ex-/Import Ratings to import .srf ratings into newly cleaned library to reclaim global ratings.