You cannot "roll-back" to an older version, since the update is NOT the cause of your problem.
Normally, is a very well known fact that the Render To Texture function in the sim has problem with two video cards. Nothing to do with GSX, other than it's one of the very few product that use it, and this has been known since a very long time, that's why, users with 2 or more video cards should always check the "Disable RTT" flag in the Addon Manager menu, and restart the sim. This will result in losing jetway and operators logos, and jetway numbers, but it's the only way to use it with more than one video card.
