1) In a large mixing bowl, combine the water, oats, maple syrup, maple flavor, butter, salt, and cinnamon. Let cool to lukewarm; this will happen naturally as you stir.
2) Add the flours and yeast, stirring to form a rough dough. Knead (about 10 minutes by hand, 7 minutes by machine, or on the dough cycle in the bread machine), enough to make a nicely springy dough.
3) Transfer the dough to a lightly greased bowl or large (8-cup) measuring cup, cover the bowl or cup with plastic wrap, and allow the dough to rise for 60 to 90 minutes. It should become very puffy, and just about double in bulk.
4) Gently deflate the dough, and shape it into an 8" log. Place it in a lightly greased 8 1/2" x 4 1/2" loaf pan. Cover the pan, and set the loaf aside to rise till it's crowned about 1" over the rim of the pan, about 60 to 90 minutes. Towards the end of the rising time, preheat the oven to 350°F.
5) Gently brush the top of the risen loaf with water, and sprinkle with maple sugar.
6) Bake the bread for 35 to 40 minutes, tenting with foil after about 15 minutes to prevent over-browning. The interior of the fully baked loaf should read 190°F on an instant-read thermometer.
7) Remove the bread from the oven, and after 5 minutes turn it out of the pan onto a rack to cool. Allow it to cool fully before slicing.