In medium bowl, combine graham cracker crumbs, melted butter and sugar until well mixed. Press lightly into bottom (compressing too hard will make it hard to cut) of a 9 inch springform pan (may, also, use a 9x13 inch pan). Bake 6 minutes, until set. Cool completely.
For the butter brickle: Preheat oven to 400 degrees.
In a large bowl, combine flour, oats, brown sugar, 1/2 cup melted butter and pecans until well mixed. Lightly pat onto a baking sheet. Bake 10 to 15 minutes, until light brown. Crumble while still hot. Cool completely.
For the filling: in the meantime, in large mixing bowl, beat cream cheese until smooth. Beat in condensed milk until well blended. Fold in whipped topping.
Spread half of the cheese mixture over the crust in the springform pan. Sprinkle half of the prepared butter brickle over the cheese mixture and spread half of the caramel sauce over that. Repeat layers. Freeze for at least 4 hours or overnight until firm, remove pan sides and serve cold. If the caramel sticks to the side, try dipping your knife into hot water and running it around the rim of the pan to loosen.