I tried to add Cluster as a release using Lukáš Lalinský's plug-in[1].

[1]: http://musicbrainz.org/doc/MusicBrainz_Picard/Plugins

Server returns HTTP 500 every time, with this error description:

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Error:

Caught exception in MusicBrainz::Server::Controller::ReleaseEditor::Add->add "Not an ARRAY reference at lib/MusicBrainz/Server/Wizard/ReleaseEditor.pm line 1518."

Stack trace:
line 1518 MusicBrainz::Server::Wizard::ReleaseEditor
line 308 MusicBrainz::Server::Wizard
line 125 MusicBrainz::Server::Wizard
line 92 MusicBrainz::Server::Wizard::ReleaseEditor
line 23 MusicBrainz::Server::Controller::ReleaseEditor::Add
line 298 MusicBrainz::Server
line 298 MusicBrainz::Server
line 298 MusicBrainz::Server
line 262 MusicBrainz::Server

Request data:
$VAR1 = {
'query_parameters' => {},
'body_parameters' =>

{ 'mediums.-1.track.4.name' => 'Zwiespalt', 'mediums.-1.track.4.length' => '497188', 'mediums.-1.track.2.name' => 'Monk 2 Niyo', 'name' => 'Mouvement', 'mediums.-1.track.1.length' => '1030478', 'mediums.-1.track.3.name' => 'Herbst', 'mediums.-1.track.0.name' => 'Mouvement', 'mediums.-1.track.5.length' => '521717', 'mediums.-1.track.0.length' => '479947', 'mediums.-1.track.1.name' => 'Abschied', 'mediums.-1.track.2.length' => '298736', 'mediums.-1.track.3.length' => '523023', 'mediums.-1.track.5.name' => 'Reminders', 'artist_credit.names.0.artist.name' => 'Sebastian Schunke Orchestral Expression' }

};

URL: http://musicbrainz.org/release/add
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