The problem cannot possibly caused by the GSX update, since GSX doesn't change *any* file in the simulator, with the one and only exception of the .BGL which contains the default jetway model, but that cannot obviously cause something like that.
Other than that, NO files in the sim are altered, the Prepard3d.cfg is not touched, the Shaders are not touched, no other files and textures of the sim are changed so no, it's not the GSX Update, that's for sure.
It LOOKS like you have a problem with Shaders (which we don't touch), so you might try to recreate them, by removing this folder:
%LOCALAPPDATA%\Lockheed Martin\Prepar3D v4\Shaders
Start the sim, and wait a couple of minutes for the black screen to go away.
