Preheat oven to 375 degrees.
Wash squash and use a vegetable peeler to remove the rind.
Microwave squash for 2-3 minutes to soften. Allow to cool; cut off ends and discard. Cut squash in two at the neck, creating a narrow end and a round end. Cut round end in half and scoop out seeds with a spoon. Cut both ends into 3/4 inch, even-size cubes.
Coarsely chop walnuts. Set aside
In a large bowl, add squash. Toss with oil, sage, salt and ground black pepper.
Spread squash evenly on a baking sheet. Roast until tender, stirring once, about 35 minutes.
In a small skillet over medium heat, melt butter. Add walnuts and cook and stir until fragrant, about 2 minutes. Remove from heat. Stir in cranberries and maple syrup.
Gently toss cooked squash with cranberry mixture.