Madman 2H2K

I'm pretty sure you have to have the original module installed in order for A-10C II to work

Same here; Callsign: Madman2H2K Prefered Aircraft: A-10C, F-15C, UH-1H Side: Blue

Just as Flaming Cliffs 3, the A-10C module is part of DCS: World, the component holding all of the different modules together. If you're using Flaming Cliffs 3 with DCS: World, it is possible to run the A-10C module along with it. If you are still using the standalone version of Flaming Cliffs 3, I don't think it is possible to play the A-10 in this.