Preheat oven to 325 degrees F (165 degrees C). Grease a 9x13 inch baking pan.
Slice zucchini lengthwise into very thin slices using a peeler. Sprinkle slices lightly with salt and set aside in a colander to pull the moisture out of the zucchini.
Cook the ground beef and black pepper in a large skillet over medium high heat for about 5 minutes. Add in the green pepper and onion; cook until meat is done. Stir in the tomato paste, tomato sauce, wine, basil, and oregano, adding a small amount of hot water if the sauce is too thick. Bring to a boil then reduce heat and simmer for about 20 minutes, stirring frequently.
In another bowl stir egg, ricotta, and parsley together.
Assemble lasagna, spread 1/2 of the meat sauce into the bottom of a greased pan. Next layer 1/2 the zucchini slices, 1/2 the ricotta mixture, all of the spinach, followed by all of the mushrooms, and 1/2 the mozzarella cheese. Repeat by layering the remaining meat sauce, zucchini slices, ricotta mixture, and mozzarella. Spread Parmesan cheese evenly over the top and cover with foil.
Bake for 45 minutes. Remove the foil and bake at 350 degrees F (175 degrees C), for an additional 15 minutes. Let stand for 5 minutes before serving.