Heat oven to 375°F. Spray 11x7-inch (2-quart) glass baking dish with cooking spray. In 10-inch skillet, heat oil over medium heat until hot. Add celery, onions and garlic; cook 1 to 2 minutes, stirring occasionally, until vegetables begin to soften.
Stir in peas, imitation crabmeat and mushrooms. Cook 3 to 5 minutes, stirring occasionally, until thoroughly heated. Reserve 2 tablespoons of the cheese for topping. Stir remaining cheese and the pasta sauce into crabmeat mixture; cook 3 to 5 minutes, stirring occasionally, until thoroughly heated and cheese is melted. Spoon into baking dish.
Unroll dough into 2 long rectangles; press perforations to seal. Place rectangles over crabmeat mixture; pinch center edges to seal. Press outside edges of dough to edges of baking dish. Cut several slits in dough for steam to escape. Sprinkle with reserved 2 tablespoons cheese.
Bake 15 to 20 minutes or until thoroughly heated and crust is golden brown. To serve, cut into squares.