From reading your description of the walls, it sounds like you have the same kind found in my 1900 house - shiplap. Houses were often built with shiplap walls up into the 1940's. I have also seen walls lathed for plaster - this is completely different. The cloth hung behind the wallpaper is probably grasscloth - A very expensive fabric these days. I also found no info on covering shiplap walls, so I developed my own solutions (without drywalling) If you wouls like more info, feel free to e-mail me.