Coat a large nonstick skillet with cooking spray; place over medium-high heat until hot. Cook ground round and onion over medium heat until browned, stirring until meat crumbles. Drain and pat dry with paper towels. Wipe drippings from skillet with a paper towel.
Return meat mixture to skillet. Add spaghetti sauce, water, and salt; bring to a boil. Reduce heat and simmer, uncovered, 10 minutes; set aside.
Drain spinach; press between paper towels. Combine ricotta cheese, 1/2 cup mozzarella cheese, egg substitute, and pimiento; stir in spinach.
Coat a 13- x 9- x 2-inch baking dish with cooking spray. Spoon 1 cup meat mixture into dish. Place 3 uncooked lasagna noodles over meat mixture. Spoon one-third of remaining meat mixture over noodles; top with half of spinach mixture. Place 3 lasagna noodles over spinach mixture; spoon half of remaining beef mixture over noodles. Top with remaining spinach mixture. Top with remaining 3 noodles and remaining meat mixture.
Cover and bake at 350° for 55 minutes. Uncover; sprinkle with remaining 1/2 cup mozzarella cheese. Bake, uncovered, 5 minutes or until cheese melts. Let stand 10 minutes; serve.