Heat oven to 350. Using 1 tbsp margarine, generously grease 9 inch round cake pan or 8 inch square pan. Spread 1 cup of the apples in greased pan. Separate dough into 10 biscuits;cut each into quarters. Arrange biscuit pieces, points up,over apples. Top with remaining 1/2 cup apples.
In small bowl, combine 1 tbsp margarine,brown sugar,cinnamon,corn syrup,whiskey and egg;beat 2 to 3 minutes or until sugar is partially dissolved. Stir in pecans;spoon over biscuit pieces and apples.
Bake at 350 for 35 to 45 minutes or until deep golden brown. Cool 5 minutes. In small bowl, blend all glaze ingredients, adding enough milk for desired drizzling consistency. Drizzle over warm cake. Serve warm or cool. Store in refrigerator.