In small bowl, soften gelatin in cold water. In 2-quart heavy saucepan, stir together egg yolks, sugar, 1 tablespoon of the orange peel, orange juice, lemon juice and 1/8 teaspoon of the salt. Cook over low heat, 8 to 10 minutes, stirring constantly, or until slightly thickened; remove from heat. Add 2 tablespoons of the butter, gelatin and 1 teaspoon of the vanilla; stir until butter is melted. Fill large bowl with ice water; place saucepan in water. Cool egg mixture, stirring occasionally, about 10 minutes or until thickened.