In a 2-quart microwave-safe bowl, combine onion, ginger root, and oil; microwave on medium for 1 minute. Stir in garlic, curry powder, cinnamon, and turmeric; cover and microwave on medium for 1 minute. Reserve 1/2 cup chopped tomatoes; add remaining tomatoes, the eggplant, zucchini, water, and salt to onion mixture. Cover and microwave on high for 6 minutes. Stir, cover, and microwave on medium for 5 minutes. Add reserved tomatoes, the raisins, and honey: stir, cover, and let stand 5 minutes. Meanwhile, prepare couscous following package directions. To serve, mound some of couscous onto each of 4 serving plates. Make a well in center of couscous and fill each with stew mixture.