Heat oven to 350°F. Spray 11x7-inch (2-quart) glass baking dish with nonstick cooking spray. Cook pasta shells to desired doneness as directed on package. Drain; cover to keep warm.
Meanwhile, heat olive oil in large skillet over medium heat until hot. Add bell pepper and onion stir-fry, and garlic; cook and stir 2 to 3 minutes or until crisp-tender. Add eggplant and zucchini; cook and stir 3 minutes.
Stir in tomatoes with tomato oil, olives and 1/4 cup of the pasta sauce. Cook until thoroughly heated, stirring frequently. Stir in 1/2 cup of the cheese.
Fill each cooked pasta shell with about 1/4 cup vegetable mixture. Place in sprayed baking dish. Spoon remaining pasta sauce over shells. Cover with foil.
Bake 30 minutes. Uncover baking dish; sprinkle with remaining cheese. Bake uncovered 5 to 10 minutes longer or until bubbly and cheese is melted.