You can not add any more albums. Just add Motörhead's album with the musicbrainz_releasegroupid 797cb50d-cda1-43b4-a0c6-e1a2bd60ae7b. But it does not work you can always add it again and it is then "ablum added to Motörhead" but in the list it does not exist. And you can enter the number again and again it never comes "already existing in the DB"
McVicar