"Cracking" grains is a separate problem; one can buy dedicated devices. Or improvise, e.g. an industrial blender or a Thai mortar and pestle.
I like to get the grain size down on something like corn, whatever they say. Or, were I to dare using just the KoMo, I'd do two passes, starting very coarse.
My first grain mill was completely manual. Enough flour for pasta required twenty minutes and a shower. I keep it for exactly problems like turning corn into polenta.
A related problem: If one cooks with turmeric, there are actually several varieties available dried e.g. at Kalustyan's. North India favors one, the south favors another. There is a spectacular difference grinding turmeric in a spice grinder, even to save months at a time. However, one needs to smash the turmeric down to a manageable size or it destroys the grinder. I use a mortar and pestle (and find pieces 30 feet away).