1. Soak 12 (10-inch) wooden skewers in water 30 minutes to prevent burning.
2. Prepare grill to medium-high heat.
3. To prepare salsa, combine first 12 ingredients; set aside.
4. To prepare spiedini, thread chicken and zucchini alternately onto each of 12 (10-inch) skewers. Coat spiedini with cooking spray; sprinkle evenly with 1/4 teaspoon salt and 1/8 teaspoon pepper. Place on grill rack; grill 6 minutes or until done, turning once. Serve with salsa.