I am using Spotify 18.104.22.168 version on Windows 10 Mobile 10.0.15254.401 build (latest one).
When I play playlist (local or global) app is playing the first song only, then it stops. I cannot also press "Next" button (|>) - it does not jump to next song.
What I also found that after play of playslit queue contains only first song.
Playing Radio, Albums or Artists songs works well.