Stir boiling water into gelatin in large bowl at least 2 minutes until completely dissolved. Stir in cranberry sauce until melted. Stir in cold water. Refrigerate about 1-1/4 hours until slightly thickened (consistency of unbeaten egg whites). Gently stir in mandarin oranges.
Meanwhile, stir together graham cracker crumbs, 1/4 cup sugar and melted butter in a 13"x9" pan. Press firmly onto bottom. Refrigerate until ready to fill.
Beat cream cheese with remaining 1/4 c sugar in large bowl with whisk until smooth. Gently stir in whipped topping. Spread evenly over crust. Spoon gelatin mixture over cream cheese layer. Refrigerate 3 hours until firm. Garnish with additional whipped topping.