To prepare sauce, combine the first 5 ingredients in a food processor; process until smooth. Strain berry mixture through a fine sieve over a bowl, reserving liquid; discard solids. Cover and chill.
To prepare topping, combine 1 cup each raspberries, blueberries, and blackberries in a large bowl. Add brown sugar, orange-flower water (if desired), and orange rind; toss gently to combine. Cover and chill.
Preheat oven to 425°.
To prepare corn bread, lightly spoon the flour and cornmeal into dry measuring cups, and level with a knife. Combine flour, cornmeal, 1/3 cup granulated sugar, baking powder, and salt in a large bowl, stirring with a whisk. Add milk, butter, oil, and egg; stir with a whisk.
Pour batter into an 8-inch square baking pan coated with cooking spray. Bake at 425° for 15 minutes or until corn bread is lightly browned and a wooden pick inserted in center comes out clean. Cool in pan 10 minutes on a wire rack; remove from pan. Cool completely on wire rack. Cut corn bread into 9 squares.
Spoon about 1 tablespoon sauce onto each of 9 plates, and top with 1 corn bread square. Top each corn bread square with about 1/4 cup fresh berry topping. Spoon about 1 tablespoon whipped topping over each serving.