Peel and cut the squash into 1/2" to 3/4" cubes.
Spray a casserole dish (use about a 1 1/2 to 2 quart size with a lid), with non-stick cooking spray.
Mix all the ingredients together, except the butter, and pour the mixture into the prepared casserole.
Dot with butter.
Cover and microwave on high power for about 4 minutes.
Stir, cover, and microwave on high power for about 4 more minutes, or until the squash and apples are tender and can be easily pierced with a fork.
If additional cooking is needed, microwave on high for 1 minute increments, stirring and testing with a fork after each minute.
Let stand for 2 to 3 minutes before serving.