Bring about 4 quarts of water to a full boil, adding a little olive oil to water. Add macaroni and cook about 7 minutes, until al dente. Drain macaroni thoroughly and return to large pot.
Chop apples into small chunks and place into bowl. Sprinkle with lemon juice.Add sugar, cinnamon and nutmeg to the apple and toss gently by hand to coat thoroughly. Gently add the apple pieces to the cooked macaroni in big pot.
Put butter into medium saucepan on low heat. When butter is melted, slowly add flour, stirring constantly till smooth. Gradually stir in milk and half and half. Move heat to medium. Continue cooking, STIRRING CONSTANTLY, till mixture comes to a boil and sauce thickens. Remove from heat.
Add 1 cup of each of the cheeses, stirring gently until all the cheese is melted and sauce is smooth. Add salt and pepper to taste. Fold cheese sauce gently into the macaroni/apple mixture, making sure all macaroni and apples are covered.
Pour complete mixture into buttered baking dish. Top with 1/2 cup cheese and butter pieces. *NOTE: at this point if you like you can cover dish with foil and refrigerate until you're ready to cook it.
Preheat oven to 350.
Bake, uncovered, at 350 for 35-40 minutes until cheese is melted and golden brown. Let stand 5 minutes before serving so that cheese can set. Garnish with saved apple wedges.