Coat inside of Crockpot™ slow cooker with nonstick cooking spray. Place ribs, marmalade, barbecue sauce, soy sauce, horseradish, mustard, garlic and salt into slow cooker. Cover; cook on LOW 6 hours.
Remove ribs to serving platter; cover loosely with foil to keep warm. Turn slow cooker to HIGH. Stir water into cornstarch in small bowl until smooth. Whisk into slow cooker. Cover; cook on HIGH 15 minutes or until thickened. Serve ribs with sauce.