1. Crust: Lightly spray the bottom and sides of a 9-inch spring form pan with non-stick cooking spray. Finely chop ½ cup of the almonds, set aside. Put the cookies into a sealable plastic bag and crush them into fine crumbs by rolling over them with a rolling pin. Transfer the crumbs to a large bowl and mix in the chopped nuts, cinnamon and butter. Press the crumbs in an even layer into the bottom of the pan. Top the crust with 1/4 cup sliced almonds so that some are in the crust and some sitting on top of it. Refrigerate.
2. Filling: Sprinkle the gelatin over the orange juice in a small saucepan, let stand 1 minute. Heat over low heat until gelatin is melted, set aside. Grate 1 tsp. zest from the orange and set aside. Beat the cream cheese on medium speed until smooth 3-5 minutes in the bowl of an electric mixer fitted with the whisk attachment. Beat in condensed milk; scrape down the bowl after addition. When mixture is smooth, stir in melted gelatin and grated orange rind. Spoon the filling over the crust, tapping the sides of the pan to even the filling out. Refrigerate 2 hours or until set.
3. Peel the rind from the rest of the orange, place it on a cutting board and slice it into ¼-inch thick rounds. Top the cake with the orange rounds and remaining ¼ cup sliced almonds.