[dvirtz]

Please try this test version with oauth authentication (like youtube addon):
https://app.box.com/s/lb9wu4bmfsse3zgdfekgc2it9e50qvru

Doesn't work for me on Kodi 18. 
The menu only has "Listen Now" and "Browse Stations" and clicking any of them produces 403 errors.

The version without OAuth do work though.  

Thanks for testing. Have a new version:
plugin.audio.googlemusic.exp-2.0beta2 

I had to delete userdata but then it worked perfectly. Thanks!