For the experiment of just seeing if this works I mounted a sample game on the side of the fridge. The rectangular bit of graph paper is some gamer paper cut to 15X26 which is the space between the two opposing deployment zones. My Terrain is all felted so is extra thick, but the neo-dymium magnets still hold it up, but just barely. I did use a couple YMG measuring sticks which weren't felted and which worked quite well, so I know it will work.
This is a closer commanders eye view. The magnets are really strong. I will post ordering info and what not soon.