When playing the music back from the beginning when further on through the score how do i get the playback line to go to the start automatically?
The shortcut Shift+Alt+Space plays back from the start of the current flow. You can also assign a keyboard command to Play > Navigate To Start (in the Key Commands page of Preferences) to move the playhead to the start of the flow.
I got that to work but the page did not go back to the start as well, is this possible?
No, I’m afraid at the moment Dorico doesn’t follow the score during playback automatically, but this is of course planned and I hope it will be implemented soon.