In the bowl of a stand mixer, combine 2 cups of the flour, the sugar, dry yeast and salt.  Stir until blended.  In a separate bowl, combine the water, sweet potatoes and the butter.  Microwave the mixture on high in 15 second increments until very warm, but not hot (120º to 130ºF).  The butter will not melt completely.  Add the liquid mixture to the flour mixture along with the egg.

Beat the mixture on medium speed for 2 minutes, scraping the bowl occasionally.  Continue adding in flour, 1/2 cup at a time, until the dough just pulls away from the sides of the bowl. 

Lightly flour a work surface and turn the dough out.  Knead until the dough is elastic and smooth, about 6 to 8 minutes.  Cover with a towel and allow the dough to sit for 10-15 minutes. 

While the dough is resting, prepare the filling.  Combine the brown sugar and pumpkin pie spice in a small bowl. 

Roll the dough out into a 15x12-inch rectangle.  Spread the butter over the dough, stopping about 1/2-inch from the sides.  Sprinkle the sugar/spice mixture evenly over the butter.  Starting at the long end of the rectangle, roll up tightly.  Pinch the ends to seal.  Cut the log into 12 even pieces and place cut side up in a greased 13x9-inch baking dish.  Cover the dish and allow the rolls to rise until doubled, about 45 minutes.

Heat the oven to 350ºF.  Bake the rolls until they are golden brown, 20-25 minutes.  Cool the rolls on a wire rack for at least 20 minutes.

To make the icing, beat the cream cheese and the butter together.  Beat in the powdered sugar, about 1/2 cup at a time.  Beat in the orange extract.  Add enough orange juice to make it the right consistency.  Spread the icing over the rolls and serve.