I only use FSX-SE with A320 FSL, I know as working outside FSX, GSX can't make FSX crash, but maybe some objects created can.
This kind of hard freeze cannot be caused by GSX. Or, more precisely, if we really had a corrupted object, it would crash *everywhere*, not on some airports. If the airports had mistakes like issues with their AFCAD, what would usually happen, is that Couatl would give you an error log with some kind of explanation and, in the worse case, Couatl.exe could possible crash itself, but it cannot bring down FSX, since it doesn't have any access to its process or its memory.
Now, it's might be possible a corrupted texture from an operator that appears only there, might crash the sim, although crashes due to corrupted textures are not such hard freezes, but normal errors usually in FE.DLL or TERRAIN.DLL or GD2.DLL. However, I checked the scoring assignment, and I see that at LIEE, for example, there are supposed to be only 3 operators at maximum score: Are Group, Alitalia and Meridiana.
So, I downloaded the scenery ( I guess it's the one on Avsim, right ? ), tried with all of them, and no crashes of any kind.