Preheat oven to 350 degrees. Into large bowl, beat softened cream cheese with mixer. Add the eggs, sugar, cocoa and vanilla extract; beat well with mixer, until light and fluffy. Pour into crust. Smooth the top with spatula. To prevent overbrowning, cover edges of cheesecake with foil or pie crust shields. Bake until firm, about 35 - 40 minutes. Knife inserted in middle should come out a little messy, and the content should not be runny. Let cool on wire rack. (This takes about 1-1/2 hours.) Refrigerate at least 8 hours. Then top with cherry topping and confectioner's glaze before serving.
Pit the cherries and cut into fourths. Put them in a saucepan with the water and cook at medium-heat for 10 minutes, stirring occasionally. Into a small bowl, mix together the sugar and cornstarch or arrowroot powder. Add this to the cherries and cook until thickened, about 5 minutes. Cool or chill; then put topping on cheesecake before serving.
Make a confectioner's glaze: Put 1-1/2 Cups powdered sugar, 2 tablespoons water, and 1/2 teaspoon pure vanilla extract in a bowl. Stir together; drizzle on top of cherry topping.