I've uploaded a new version of the DeDuper script which I think will do the trick. The version as uploaded has a new control variable PrefKind currently set to False. You should change this to True and then edit the PrefKinds value, if needed, to reflect your file type priorities. Multiple file extensions can be listed with the later having higher priority over earlier ones or any not listed. If both files being compared have the same file type, or neither is in the list of preferred types then the choice of which to keep reverts to largest or smallest as controlled by KeepAlt.
Please backupbefore use and test on a small batch first to make sure that the right files are preserved. If by any chance the script cleans the wrong files restore the tracks and the iTunes Library.itl database from the backup and either adjust your settings or ask for further help.
tt2