Preheat oven to 400 degrees. Poke holes with a fork in pie crust all over. Place in oven until light golden (about 6-8 minutes). Take out of oven, and set aside. Turn oven to 350 degrees.
Beat cream cheese until fluffy. Add sugar, salt, egg, lemon juice and vanilla, mix until smooth. Pour into pie crust and bake for 20 minutes at 350 degrees. Take out of oven and turn oven to 400 degrees.
Meanwhile, while pie is cooking, take the Blueberries and drain into a large measure cup. Combine syrup, cornstarch and half of the sugar.
In a medium saucepan over medium heat, add cinnamon, and stir constantly until thickened.
Remove from heat and gently stir in walnuts and Blueberries, add butter and set aside.
After 20 minutes, remove pie from oven, turn oven to 400 degrees. Let pie rest about 2 minutes. Pour Blueberries mixture over the cream cheese, spreading evenly (you may have some left).
Continue baking in 400 degrees oven for 20 minutes, or until crust is brown. Remove from oven and place on a rack for 2-3 hours before serving. Top with whipping cream if desired.