Preheat the oven to 425 degrees F (220 degrees C).
Rub oil over squash and season with salt. Place on a rimmed baking sheet and add water.
Bake in the preheated oven until softened, about 20 minutes.
Meanwhile, combine butter, honey, cinnamon, garlic, oregano leaves, orange peel, and paprika in a small saucepan over medium heat. Heat sauce until combined, 1 to 3 minutes.
Remove squash from oven and reduce heat to 400 degrees F (200 degrees C). Allow squash to cool for 5 minutes.
Slice squash partway through vertically, leaving the bottom portion attached. Drizzle with 1/2 the sauce. Return to the hot oven and bake 10 minutes more.
Remove from the oven and press gently on the squash to separate slices. Drizzle 1/2 of the remaining sauce on top and return to the hot oven. Bake 10 more minutes.
Remove from oven and tuck oregano sprigs between slices or lay on top. Sprinkle with cranberries and pistachios and drizzle with remaining glaze.
