Trim fat from meat. If necessary, cut roast to fit into a 3-1/2- or 4-quart slow cooker. Place meat in the cooker. In a bowl combine water, raisins, steak sauce, balsamic vinegar, sugar (if desired), tapioca, pepper, Jamaican jerk seasoning, and garlic. Pour mixture over roast.
Cover and cook on low-heat setting for 8 to 10 hours or on high-heat setting for 4 to 5 hours. Skim fat from the cooking liquid. Serve beef with the cooking liquid and, if desired, hot cooked rice. Makes 6 servings.