I had the same problem, tried the repair option, no go, then I remembered a post from the very beginning of the CS757, that it's not compatible with FSUIPC  if you use it to do your control calibration. The reason is the Autopilot does not override the controls, so it ends up fighting the controls all the way up. at lower altitudes it can compensate for it, but as the air gets thinner and thinner the higher you climb, it gets harder and harder to do, and the lateral controls get more and more slugish, until past FL350 it can't compensate anymore and you lose all lateral controls. The solution is to turn off all FSUIPC joystick calibration when flying the CS aircraft. (Not sure if the 777 or later aircraft are affected by this) This is why it worked when the OP removed FSUIPC.