In a small saucepan combine gelatin and sugar; add 2/3 cup of the water. Cook and stir over medium heat until dissolved. Remove from heat. Stir in remaining water and lemonade concentrate. Divide mixture in half, transferring each to a medium bowl. Stir red food coloring into one portion of the mixture. Cover and chill about 1-1/4 to 1-1/2 hours or until mixtures mound.
In a chilled bowl beat whipping cream with an electric mixer on medium speed until soft peaks form (tips curl); set aside.
Wash beaters. Beat plain lemonade mixture with electric mixer on medium speed about 30 seconds or until light and foamy. Beat pink mixture until light and foamy. Fold half the whipped cream into each lemonade mixture.
Carefully layer plain mixture and pink mixture into 6 small serving glasses or dessert dishes, dividing evenly.
Cover and chill at least 2 hours before serving. Garnish with fresh berries, and if desired, citrus slices and lemon peel curls. Makes 6 servings.