Preheat over to 350 degrees. Coat 8x4-inch pan with cooking spray. Set aside. In large bowl, blend sugar and margarine with electric mixer at high speed one minute. Set aside. In medium bowl, combine cake flour, 1 tsp. baking powder and salt. Set aside. In small bowl, mix together 1 T. water, 1 T. vinegar, and 1 tsp. baking powder. Add to margarine mixture, beating well. Beat in flour mixture, alternating with orange juice. Beat in orange rind and vanilla extract. In small bowl, mix together 2 T. water, 2 T. vinegar, and 2 tsp. baking powder. Fold mixture into batter. Blend 30 seconds on medium speed. Pour into prepared pan. Bake 55 minutes, or until toothpick inserted in center comes out clean. Cool in pan 10 minutes. Transfer to wire rack to cool completely. Drizzle Creamy Glaze over top of loaf.
Creamy Glaze: In medium bowl, beat all ingredients together with electric mixer until smooth.