I don't see this as a hurdle for RGM specifically. TRIAD would probably absorb most of the rework required to run thier engines on an ethanol blend.
Corn derived ethanol as a fuel, however, is a really dumb idea. It is not a "green energy" - overall more CO2 and CO is released in it's production than what is saved. It's a boondogle to boost farm subsidies for mega farms that grow corn. Ethanol can be a "green" fuel, but not when produced from corn. Sugar-can based ethanol, like what will be used in Indy Cars next year is good. But biodiesel is a much better alternative fuel in the short term.
Or even better than sugar cane (or suger beets) may be using the waste, i.e. corn stalks, wheat stubble, prairie grass, etc. My gut feeling is that, for a lot of these, it takes a "gallon" of energy (or more) to produce a gallon of ethanol. Everyone involved has an agenda to skew the data to their particular view or product, so it's hard to know for sure.
Ditto Alan, not only is corn ethanol NOT green, it wreaks havoc on engines. Lower horsepower, poor mileage, unstable. It was never tested on marine or small engines and really fouls them bad. While it does run in your automobile, it can't be good given all the problems we see in outdoor power equipment.