I'll go out on a limb here and say that I think the major difference is the plug itself where the coil is made from some material that has a catalytic reaction with petrol or possibly something in the oil seeing that the
type of oil seems to be critical. Having just read CL's article on that Enya he came to much the same conclusion regarding the special oil needed too. I can't see the head itself making any difference because once the fuel is ignited (either petrol or methanol) they burn much the same. Combustion chamber shapes (and to a lesser extent even compression) can vary wildly from the old baffled piston type to smooth Schneurle ported heads yet all these types will run quite happily on either fuel so long as they have the correct ignition (although spark is somewhat better with methanol but more complicated).
The carb though has to be a little different to a normal carb because it has to regulate the fuel flow within much stricter limits than you can get away with using methanol. Basically this just needs a more finely tapered needle along with fine threads but still leaves the problem of avoiding fuel draw change during flight from full to empty tank and attitude changes of the model. I have no idea how they've overcome this especially with apparently a larger carb bore than usual which would reduce fuel draw and no means of regulating fuel pressure.
However if it works as claimed then it's very interesting. I might add that I have a Norvel 15, 25 and 40
.