1. Coat a large nonstick skillet with cooking spray; place over medium-high heat. Add roast; cook until browned on all sides. Place roast in a 4- to 5-quart electric slow cooker coated with cooking spray.
2. Combine cranberry sauce and next 3 ingredients; pour over roast. Cover and cook on low-heat setting for 8 hours or on high-heat setting for 4 to 5 hours. Remove roast from sauce; cover roast, and keep warm.
3. Combine water and cornstarch, stirring until smooth. Stir cornstarch mixture into sauce in slow cooker. Pour mixture into a 1-quart microwave-safe glass measure. Microwave at HIGH 2 minutes, stirring after 1 minute. Serve roast with gravy.