Establecer que determinados podcasts se muestren como programas de televisión en iTunes, utilizando AppleScript

Estoy usando un grabador de TV online para grabar programas de TV. Esas grabaciones se descargan como podcast en iTunes. Mi siguiente Applescript debería coger esos podcasts, actualizar algunos campos de información y finalmente marcarlos como "programa de TV" para que aparezcan en "Programas de TV" en iTunes.

Funciona muy bien, sólo la parte en la que quiero poner el tipo de vídeo en programa de televisión no parece funcionar.

set video kind of aTrack to TV show

También eché un vistazo a el script de este Doug que hace algo parecido y no encuentro ninguna diferencia.

Aquí está mi script completo:

on matchRegExp(regex, txt, |caseSensitive?|)
    if |caseSensitive?| then
        set ci to "i"
    else
        set ci to ""
    end if
    set theRubyOneLiner to quote & "s = '" & txt & "'; s =~ /" & regex & "/" & ci & "; puts Regexp.last_match.to_a" & quote
    set theCommand to "ruby -e " & theRubyOneLiner
    set theMatchData to do shell script theCommand
    set tid to AppleScript's text item delimiters
    set AppleScript's text item delimiters to character id 13 -- new line
    set theMatchData to the text items of theMatchData
    set AppleScript's text item delimiters to tid
    theMatchData
end matchRegExp

tell application "iTunes"
    set myLib to library playlist 1

    set pods to every track of library playlist 1 whose genre is "Podcast" and album is "Online Videorecorder"

    set ofi to fixed indexing
    set fixed indexing to true

    with timeout of 3000 seconds
        repeat with aTrack in pods
            set desc to long description of aTrack

            try
                set episode to last item of my matchRegExp("(Folge|Episode) (\\d+)", desc, true)
                set season to last item of my matchRegExp("(Staffel|Season) (\\d+)", desc, true)
            end try

            set series to name of aTrack
            set title to description of aTrack
            set cat to category of aTrack

            try
                set video kind of aTrack to TV show
            on error m
                log m
            end try

            set episode number of aTrack to episode
            set season number of aTrack to season
            set show of aTrack to series
            set episode ID of aTrack to title
            set description of aTrack to desc
        end repeat
    end timeout
    set fixed indexing to ofi

end tell