In large skillet, saute the mushrooms, pecans, and onion in 4 tbsp butter until tender. Stir in the rice, apricots, parsley, salt, pepper, and cayenne.
Spoon about 3/4 cup rice mixture into each hen; tie legs together with kitchen string. Place hens, breast side up, on a rack in a shallow roasting pan. Melt remaining butter; brush over hens.
Bake, uncovered, at 350 degrees for 1-3/4 to 2 hours or until a meat thermometer reads 180 degrees for hens and 165 degrees for stuffing. In a small saucepan, warm preserves and vinegar; spoon over hens. Bake 15 minutes longer.