Weird Walls

The walls in this room and all of the 2nd story are made of a fiber board nailed over the studs.  I'm going to put up textured wallpaper over the walls.  The old cloth tape and wallpaper that is covering the nails and seams is cracked and bulging out, so I have to tear it off and redo it.
Here is what it looked like before.

 This is what it looked like after the tape was removed.  It shows the original material and the nails.

This is what it looks like after the 'tape and mud'.  Pretty good for a beginner!