This is disappointing, they must have turned off there validation software. Like you I have a couple RealAir products that I am not going to be able to re-install if I have to rebuild my system.
They had mentioned doing something so those who had purchased there products could still install them but it appears that has not happened. For someone like me who purchased from them directly they have an email they could use to notify me that update was available but for those who purchased DVD's I don't know how they could expect to find you.
I had hoped they would have turned there installers into freeware and placed them on flightsim.com or SOH but that did not happen either.