The previous owners appear to have lined two of the bedrooms with lining paper (or maybe paintable wallpaper), and painted one of the walls in each room in navy blue and the remainder in white. In the smallest room, the plan was to repaint the whole room white to freshen it up, paint over scuffs and marks, and get rid of the dark "feature wall". It's a small room and the dark blue makes it look dark and dim. What's the best way to proceed? I don't want to take off the paper - just want to paint over it. I was planning on using Dulux supermatt to just paint over everything but read somewhere it doesn't adhere well to vinyl silk. I've no idea what the paint finish is. Any advice would be welcome.