I found two problems with android auto: 1 if spotify is in offline mode google now not found the dowmloaded song or playlist. 2 with spotify in offline mode my albums or artist list show all (not only the donwnoaded)
Me too To clarify 1. Google now isn't able to operate Spotify when Spotify is on offline mode 2. When in offline mode there is no way to manually find and play your offline music. You end up having to exit android auto, open Spotify, select the music to play then restart android auto. In other words, a bit pointless as it stands.