Puid lookup including release and media, if the recording with the puid is track 1 on the medium then the offset paramter in the track-list element is missing.

i.e
http://musicbrainz.org/ws/2/puid/315f88f8-1045-e898-45c8-bb153c5ac6d6?inc=releases%20media

look at recordingc0b7b368-ad18-481f-9184-2d92fa5799df and release 60ad15f3-a76d-42fe-b6d6-f2b01e13ce39 it says

<track-list count="2">

when it should be

<track-list count="2" offset="0">

like releases where the first track isnt the first track on the media.

This wierdness has broken my application, and maybe others like Picard so suggest this is important.