I might have gone a bit overboard on the difficulty of that maze.
I added a map on the guide: https://docs.google.com/spreadsheets/d/1nlO2owvibS5tvHbFyK83FGQc0PcGN16cWm7aq3Q4...
As for the stone doors, when you rescue a soul, you should get a colored ball that you can use to open the matching door.