Cook tortellini according to package directions. In a large skillet, heat oil over medium-high heat. Add mushrooms, squash and poultry seasoning; cook and stir 6-8 minutes or until mushrooms are tender. Add apple, apple juice concentrate, vinegar and onion; cook 2-3 minutes longer or until squash is tender., Drain tortellini; rinse with cold water and place in a large bowl. Add squash mixture, walnuts, cheese and parsley; toss gently to coat.