This goes back to duplicating the programming of a controller within the nanoKONTROL.
If it was me, I'd make fader 9 the master fader(OK, that just sounds bad..). Why? Goes with console logic, that's why.
But, screw that logic for a moment, because it's trivial.
If you want to use Fader 1 in each scene as a master dimmer/fader, you'll need to duplicate the COMPLETE configuration of that controller in each of the 4 scenes in the nanoKONTROL. If you think you've done it and still aren't seeing it, you probably forgot to duplicate the MIDI channel as well. That's an easy one to overlook.
What I suggest is you donwload the free MIDIOX program, which you can use to test stuff, and you'll see your problem quickly.
If you can CLONE the configuration of a controller on the nanoKONTROL to another controller, then you're gold. All myDMX cares about is the MIDI channel(could care less which ones you do use) and MIDI data. If you assign on the nanoKONTROL, scene 1, fader 1 to a certain MIDI channel and certain CC, and repeat ALL of that to the same controller but in different scenes, MyDMX will see what it is looking for.
Now, keep in mind, the JLCooper CS102 only uses MIDI channel 16, but by default, the nanoKONTROL uses more MIDI channels than that.
Keep looking around, you'll find it and fix it. I don't screw with my unit, I need it for ProTools so I'm not going to dink with it if I don't absolutely have to.
Oh, and don't forget to write those values to the controller. That's another one that's easy to overlook.
Honestly, I think you're SO close to getting this done that you're probably frustrated as to why you're THIS CLOSE but stil failing.
Incidentally, why do you need this master fader and why is your light guy so insistent on having a controller? Not to say you don't need a controller, but it seems he's trying to emulate a manual operation of something that can be heavily automated.