Here's List of the separate Instance BGMs put together: 1. General Walk Uni 01 ... 6. General Walk Uni 06
The background music in many areas of Zangarmarsh is Chopin's Nocturne in C-sharp Minor, Op. 27, No. 1. Zangarmarsh's music, in a slightly different version, can also be heard in the exterior parts of Ahn'Qiraj. As Ahn'Qiraj was implemented earlier than Zangarmarsh, it could mean its music has been slightly "remixed" for the new zone.