Season ribs with salt and pepper and place in a large, sealable container. Add coconut milk, 4 Tbsp. each orange and lime juice, soy sauce, brown sugar and 4 tsp. Caribbean Curry. Stir to coat ribs. Refrigerate 30 min. to 3 hours.
In a food processor, add onion, garlic, ginger, tamarind, preserves, soy sauce, Jamaican Jerk, vinegar, remaining 1 tsp. each orange and lime juice and remaining 4 tsp. Caribbean Curry powder. Chop until coarse sauce is formed, 1 to 2 min. Transfer to a bowl, cover and refrigerate.
Preheat oven to 225 degrees. Remove ribs from marinade and place meat side down on a baking rack set in a foil-lined baking sheet. Cover securely with foil, set on middle rack of oven and cook for 3 1/2 hours. Uncover and carefully turn ribs over so meat side faces up. Baste with thick coat of Caribbean sauce and cook uncovered for an additional 20 to 25 min. Let rest for 10 min. before slicing. For a caramelized texture, finish ribs on a grill at medium high heat, meat side down, 4 to 6 min. before resting and slicing.