In a small bowl, combine the flour and salt; cut in shortening until crumbly. Gradually add water, tossing with a fork until dough forms a ball. Cover and refrigerate for at least 30 minutes.
Shape into two balls; roll into two 6-1/2-in. circles. Transfer to two 5-in. pie plates. Trim pastry 1/2 in. beyond edge; flute edges. Set aside.
Place apples in a small bowl; sprinkle with the lemon juice, flour, sugar, cinnamon and salt. Toss to combine. Spoon into pastry shell. Bake at 375° for 15 minutes. Remove from the oven.
For topping, melt butterscotch chips and butter in a small saucepan over low heat, stirring constantly. Remove from the heat; stir in flour with a fork until crumbly. Sprinkle over top of apple mixture. Bake 15-20 minutes longer or until apples are tender.