Recently installed a new ROM on my Galaxy Nexus and am trying to redownload all my music from Play Music (I do have All Access, so I can't just transfer files). I need to keep them offline because I have no mobile data connection, only wifi.

When I try pressing Keep on Device in the options menu of the playlist, it gives me a toast saying "This music is only stored on this device". Also strange, where there should be an image of the pin, it is just blank. You can still press the area and it'll give you the same message. The Last Added playlist is the only thing I can't keep offline for whatever reason. I tried installing older versions of the app, but no dice (up to v5.0, since that's when all the All Access stuff was added, i think). What can I do to fix this?

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EDIT: I tried decompiling the apk and that toast string named "toast_cant_pin_side_loaded". And the function in which it is called seems to imply that the playlist is either unpinnable or had some problem while pinning.