Preheat oven to 350°F.
Line a 13×9-inch baking pan with foil and coat with nonstick cooking spray.
Combine graham cracker crumbs and melted butter; stir well. Press into prepared pan in an even layer.
Layer the walnuts, semi-sweet chocolate chips, white chocolate chips, butterscotch chips and coconut on top of the crust. Drizzle condensed milk evenly over the top.
Bake 25 to 30 minutes or until golden brown. Cool in pan completely on a wire rack. Cut into squares.