Preheat oven to 350 degrees. In a skillet, sautee the onion, scallions, celery, mushrooms, and vegan margarine. When browned, add the apple, parsley/sage, and salt/pepper. In a mixing bowl, combine the contents of the skillet with all remaining ingredients, stirring well.
Bake for approx 25 minutes, stirring once, until crust is browned but still moist.