Preheat oven to 325°. Grease and flour a 9 inch springform pan. Using fork, combine gingersnaps, hazelnuts, 3 tablespoons brown sugar and melted butter. Press mixture into bottom and two inches up the sides of the pan to form crust. With electric mixer, beat cream cheese and brown sugar until light and fluffy. Stir in pumpkin. Mix in cream, maple syrup, cinnamon, allspice and vanilla. Beat in eggs, one at a time, mixing until smooth. Pour batter into prepared crust. Bake in preheated oven for 90 minutes, or until center of cheesecake is set. Allow to cool in pan for 30 minutes, then refrigerate overnight.