Have butcher dress pig, leaving head, tail, and feet intact. Wash pig thoroughly, and pat dry. Combine 2 teaspoons salt and sage; rub body cavity with mixture. Set aside.
Combine crumbled sausage, onion, and garlic in a very large skillet; sauté until sausage is browned and onion is tender. Remove from heat, and drain well. Stir in bread cubes, chopped apple, walnuts, 1 tablespoon salt, pepper, thyme, and marjoram. Combine eggs and 1/4 cup apple cider; mix well, and add to sausage mixture.
Stuff mixture lightly into body cavity of pig; sew opening together securely using heavy string. Place a small block of wood in pig's mouth to prop jaws open. Insert meat thermometer into pig, being careful not to touch fat or bone. Transfer whole pig to a large roasting pan. Combine melted butter and remaining apple cider; mix well, and set aside.
Bake stuffed pig at 350° for 2 hours and 15 minutes or until meat thermometer registers 170°, basting frequently with apple cider mixture.
To serve, transfer stuffing from pig to a serving dish. Transfer whole pig to a large serving platter; garnish platter with parsley sprigs and spiced crab apples. Remove wood block from pig's mouth, and insert apple between jaws. Place maraschino cherries in eye sockets. Cut off legs; carve pork along spine, cracking backbone.