Bumpy Plastered Wall

Concerning the bumpy plastered wall: I have used a stiffening fabric which is sold at wallpaper stores as a base, then either papered or painted it. It's thick, very easy to apply and spans both bumps and grooves such as those found in paneling. I have papered over the fabric (it's brand name is Pelon and it's the same stiffner used in men's shirt collars and shirt front linings), painted over it and done faux finishes with excellent results.