the ad blue is some nasty shit. it has all kinds of health risks associated with it and you definitely do not want to spill it. it crystallizes and stains just about everything it touches. we had to flush out the hose, nozzle, and pump when we would fill cars at the dealer, otherwise it would crystallize and block up the lines and or pump.
Mercedes has made changing the coding difficult. in the good old days you could go in with the factory tool and make whatever changes you wanted. but now all the coding comes from mb usa over the internet and its a very long sting of 3 digit letter/number combos, that the module interpreters into coding. but like everything, im sure some smart guy has a work around.
have have no moto