Microwave caramels and 1 Tbsp. milk in microwaveable bowl on MEDIUM (50%) 30 sec. or until caramels are completely melted when stirred.
Pour into crust; sprinkle with nuts.
Beat pudding mixes, eggnog and remaining milk with whisk 2 min.; spoon 1-1/2 cups over nuts. Stir half the COOL WHIP into remaining pudding; spread over pudding layer in crust. Top with remaining COOL WHIP.