Preheat broiler. Arrange split eggplants flesh side down on large baking sheet. Pierce with fork. Broil 4 minutes, turn, broil an additional 4 minutes. Scoop out eggplant pulp, leaving 1/2-inch-thick shell intact. Place pulp in heavy medium saucepan, cover with 2 cups water, add 1 teaspoon Rouses salt and bring to boil. Reduce heat, cover and simmer 15 minutes. Uncover and simmer until eggplant is very tender and liquid evaporates, about 5 minutes. Remove from heat.

Preheat oven to 375°F. Brush eggplant shells with 1 tablespoon oil; place, cut side up, on a rimmed baking sheet. Do not over-crowd. Bake until shells are tender but still hold their shape, approximately 20 minutes. While shells are baking, heat 3 tablespoons oil in heavy large skillet over medium-high heat. Add onions; sauté until tender, about 5 minutes. Add boiled eggplant, shrimp and cayenne; sauté until shrimp are cooked through, approximately 4 minutes. Remove from heat. Stir in 1 cup breadcrumbs and crab meat, and season to taste with Rouses salt and pepper. Fill eggplant shells with shrimp and crabmeat mixture. Sprinkle stuffing with Parmesan cheese and remaining 2 tablespoons breadcrumbs. Bake stuffed eggplants until heated through, about 30 minutes. Let stand 5 minutes. Serve hot.