HEAT oven to 350ºF.
LINE 13x9-inch pan with foil, with ends of foil extending over sides. Mix cookie crumbs, nuts and butter; press onto bottom of prepared pan. Bake 10 min.; cool.
MICROWAVE chocolate in medium microwaveable bowl on HIGH 2 min. or until chocolate is almost melted; stir until completely melted. Stir in 2 cups COOL WHIP. Pour over crust. Let stand 30 min. or until firm.
BEAT pudding mixes and milk in large bowl with whisk 2 min.; stir in remaining COOL WHIP. Spread over chocolate layer in pan; top with berries. Refrigerate 2 hours.
USE foil handles to remove dessert from pan. Microwave caramel bits and milk in microwaveable bowl 2 min.; stir until caramel bits are completely melted and mixture is well blended. Drizzle over dessert.