Preheat the Oven: Set your oven to 350°F (175°C) and lightly grease an 8-by-8-inch baking dish.
Blend the Pumpkin Filling: In a blender, combine the pumpkin puree, coconut milk, cane sugar, cornstarch, vanilla extract, sea salt, and pumpkin pie spice. Blend until smooth and creamy. Pour the mixture into the prepared baking dish.
Add the Cranberries: Sprinkle the cranberries evenly over the pumpkin filling.
Prepare the Crisp Topping: In a medium bowl, whisk together the oats, flour, brown sugar, cinnamon, and sea salt. Add the melted vegan butter and mix until everything is well-coated.
Add the Topping: Sprinkle the oat mixture evenly over the cranberries, gently pressing down to form an even layer.
Bake: Place the dish in the oven and bake for 55-60 minutes, until the edges are bubbling and the center is mostly set.
Cool and Serve: Let the crisp cool for at least 3 hours, or overnight, before slicing and serving.