Mix vinegar, thyme, sugar, mustard, salt, pepper and garlic in small bowl. Whisk in oil. Reserve 1/3 cup. Divide remaining dressing between 2 plastic bags. Add chicken to one, and zucchini, tomato, scallions and sweet pepper to other. Marinate 20 minutes.
vegetables, 8 to 10 minutes; chicken, sausage, 20 to 25 minutes. Cool slightly. Cut vegetables and sausage in bite-size pieces; add to reserved dressing. Serve with chicken.