Default [Q] How to make Google Play Music store the music on the SD Card?

Google Play Music is installed on my TrueSmart, but stores the music for offline listening on the internal 8Gb memory. Too small! I've added a 32Gb SD-card for that music storage, but I do not find how to make it works!

By default, the Google Play Music are stored on /storage/sdcard0/Android/data/com.google.android.music/files/music, that is on the internal 8Gb memory.

I tried to create symbolic links (see http://forum.xda-developers.com/show....php?t=2538274), but without any success:
- when I try to create a symbolic link in /storage/sdcard0/Android/data/com.google.android.music, I obtain an error explaining that this SD-Card "do not support symbolic links"
- I can create a symbolic link in /data/data/com.google.android.music, that is the 1 Gb RAM. But Google Music dont use it (even when I choose 'phone' as the default storage in parameters/storage of the Truesmart).

I need help:
- to create a symbolic link on the 8Gb memory
- or, to force google music store on the 1Gb memory (and thus on the 32Gb card with the symbolic link)
- or, any better idea?

Thanks in advance!