Preheat oven to 450°F. Toss squash, olive oil, and crushed red pepper on large rimmed baking sheet. Sprinkle with coarse salt. Roast 15 minutes. Using spatula, turn squash over. Roast until edges are browned and squash is tender, about 15 minutes longer. Sprinkle with coarse salt. DO AHEAD: Can be made 2 hours ahead. Let stand at room temperature. Whisk orange juice, walnut oil, and lemon juice in large shallow bowl. Season to taste with salt and pepper. Add arugula, walnuts, and pomegranate seeds; toss to coat. Season to taste with coarse salt and pepper. Spoon warm or roomtemperature squash over salad. Drizzle with pomegranate molasses and serve. A thick pomegranate syrup; available at some supermarkets and at Middle Eastern markets, and from adrianascaravan.com.