In a medium saucepan, stir together the sugar and unflavored gelatin. Add the cranberry juice cocktail; heat and stir until gelatin is completely dissolved. Stir in 3/4 cup chopped cranberries, ginger ale, and cranberry liqueur. Turn into a 6- to 7-cup mold (cranberries will float). Cover and chill until almost set, about 60 minutes.
In a saucepan, stir together the pineapple/orange gelatin an water; stir over medium heat until gelatin is completely dissolved. Add sherbet; stir until melted and blended. Gradually blend in sour cream; whisk until smooth. Cover; chill until partially set. Stir in nuts and 1/2 cup chopped cranberries.
Spoon sherbet mixture over almost-set first layer in mold. Cover and chill until mixture is set.
To serve, line a serving plate with greens, if desired. Unmold salad onto greens. Trim salad with Frosted Cranberries, if desired. Serves 12.
Dip cranberries in light corn syrup; coat with sugar.