Mix wafers and butter well. Pat into 9x13 pan. Cool. (Save ½ cup crumbs for top) Mix 1 container of Cool Whip and marshmallows together. Put over crust. Then carefully spoon pie filling over Cool Whip. Top with 2nd container of Cool Whip and sprinkle crumbs on top.
Store in refrigerator. Keeps for a few days.