Preheat oven to 400 degress F. To prepare the crust, cream the butter and 1/3 cup sugar, and add the flour and blended until mixture resembles coarse crumbs. Pat crumbs into the bottom and 1" up the sides of a 10" springform pan. Base 10 minutes, until golden. Cool. In the large bowl of an electric mixer, cream the cream cheese 1/2 cup sugar together until blended, scraping down the sides of the bowl several times. Mix in the eggs and vanilla. Pour the mixture evenly over the baked crust. Core apples and cut into thin even slices. Arrange apple slices in overlapping layers over the cream cheese filling. Mix 1/3 cup sugar and the cinnamon, and sprinkle over top of the apples. Bake 35 minutes, until the apples are tender and the cheesecake layer is set. Cool, then chill. Before serving, spoon the warm orange marmalade over the top. This cheesecake is pretty as apple slices bake into cheesecake filling with a cinnamon glaze on top. Recipe