did u guys get a manual for the command system for your GL?

I don't think I got it, and I have no idea how to use the music registry HD or how to put songs in there.

Hi.
You can download any manual from here :

http://www.mbusa.com/mercedes/only_m...=manualsguides

There is only one link available for the owner's manual for the 2015 GL and comand is not part of it.

How do you dump music in there? it says a DVD or something? This is very confusing.

This is a 2013 - should cover it, right? I attached the PDF here but didn't look up your question. Good luck!