Filling- Beat cheeses with an electric mixer until smooth. Gradually beat in egg substitute, 1/2 cup granulated sugar and vanilla until smooth. Set aside 1 cup of cheese mixture.
Add pumpmkin, brown sugar, and pumpkin pie spice into remaining cheese mixture and beat.
Crust- Preheat oven to 350 degrees. Combine crumbs, marmalade, and 1 Tbs sugar in a bowl. Press crumb mixture into bottom and up sides of a 9-inch pie plate. Bake until crust is set and lightly browned around edges, 8 to 10 mins.
Pour half of pumpkin mixture into crust. Top with reserved cheese mixture, then with remaining pumpkin mixture.
Bake cheesecake until set, about 30 mins. Cool on a wire rack. Refrigerate until chilled. Garnish with kumquats and mint.
