Preheat oven to 450°.
Melt the margarine in a medium saucepan over medium heat. Add garlic, and sauté 1 minute. Add flour and salt; cook 30 seconds, stirring with a whisk. Gradually add milk, stirring constantly with a whisk. Bring to a boil; reduce heat, and simmer 3 minutes or until slightly thick, stirring constantly. Remove from heat, and stir in the cream cheese until melted. Set aside.
Combine ricotta, 1/4 cup mozzarella, basil, and egg white in a bowl. Combine broccoli, carrot, and bell peppers. Spread 1/4 cup sauce in bottom of an 8-inch square baking dish coated with cooking spray. Arrange 2 noodles over sauce. Spoon half of ricotta mixture over noodles; top with half of vegetables. Spoon 3/4 cup sauce over vegetables; top with 1/4 cup Parmesan. Top with 2 noodles, remaining ricotta mixture, remaining vegetables, 1/4 cup Parmesan, and 2 noodles, pressing firmly. Spoon remaining sauce over noodles, spreading to cover. Cover and bake at 450° for 25 minutes or until noodles are tender and sauce is bubbly. Uncover and sprinkle with 3/4 cup mozzarella; bake an additional 5 minutes. Let stand 5 minutes.