Hi everyone,
I would've tested it but I ain't been around.
James,
That isn't an SDK. It's the idea I mentioned much earlier, and an idea Stratobat mentioned, I think he did it in a WW&C thread in the CFS2 forum (on SimV). The basic idea is you make multiple installs of CFS2. Each install is about a different part of WW2. And it doesn't have to be WW2, or even a war! Someone uploads packs and the package replaces all the aircraft, campaigns, GSL, scenery etc if you know what I mean.
Keep watching the thread in SOH. I'm preparing a thread to post there

Happy flying,
Bombardier