Balsamic and Rosemary Scented Lamb Kabobs

1⁄4 cup balsamic vinegar
3 cloves garlic, finely chopped
2 tsp. fresh rosemary leaves, finely chopped
3⁄4 tsp. ground cumin
3⁄4 tsp. salt
1⁄2 tsp. ground black pepper
1⁄2 tsp. ground coriander
12 fresh white mushrooms
2 bell peppers, seeded and cut into cubes
1 1⁄4 lb. boneless lamb leg or shoulder, cut into cubes
1 large red onion, cut into wedges
1 large zucchini, cut into thick slices
6 (12-in.) wooden skewers, soaked in water