This script will change the file type of the selected AAC tracks--which you have previously made bookmarkable yourself with the script Make Bookmarkable--to "M4A" and file extensions to ".m4a" making them UN-bookmarkable. When used with iTunes 7 or later, each track is deleted and re-added so that it will be removed from the Audiobooks Library. Ratings, play count, last played date, skip count, and skipped date are preserved.
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Display/export a text file list of chosen tag data in library or playlist
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Display, create text file listing info of dead tracks