They created a plastic block and inserted it in the scoop so that the balls would line up in single file when multiple balls were in the airlock. Previously there was too much room in the scoop and the balls could be staggered and not sit above the solenoid correctly thus enabling them to be shot back out of the airlock. Anyone with a 3d printer should be able to create a new plastic insert. The insert was then held in place by a couple of bolts. You will have to drill holes in your old scoop for the bolts of course.

I put a strip of mylar about 1/2" wide along the top and bottom edges of my LCD. My LCD screen seems to be slightly proud in the middle to the point that I can feel the edge just slightly. While I haven't played the machine a lot, I haven't had any chipping yet either.