I purchased earlier this month, not knowing that 4.4 was released, and 4.3 was the only version that was working some other add-ons I purchased. As it stands, I don't have a 4.3 installer backed up, as I never had 4.3 installed.
I tried rolling back to 4.3 client after installing 4.4, but when I open the Sim, it hangs at the scenario setup screen trying to load the F-22. After a couple of minutes, it crashes to the desktop.
I've tried deleting the shaders folder, and prepar3d.cfg file after re-install of the 4.3 client, but no luck.