Those playfield nails are used so that when the ball drains through an outlane, it hits the nail and "diverts" towards the outhole. The ball does not slam into the apron !
Stencils - Ask Retropin (Gavin) if he has plans for this title, or if he can make you a set. He is the licensed Gottlieb stencil guy. His stencils are by far the best on the market. I've know that he has created stencils for some games to CORRECT mistakes made by other stencil manufacturers. From a professional standpoint, I can't afford to use inaccurate and badly drawn stencils. Can't wait for the full Paragon set !
With this cabinet, if the stencils are not going to be made, you can make your own using tracing paper, acetate sheets and about 50 hours of creating them. I've done it a couple of times years ago with good results.