Every time I create a new game of Pandas, there are options at the beginning to select the available weapons, walls, and 1 or 2 tanks; the former and latter options work as expected, but the walls just don't seem to work the same way (with the green backround indicating which options were chosen). I keep trying for bouncy walls, and get either no walls at all, or a wall that just doesn't bounce. Is there a method to the madness?