OK, I figured out a few things. I disabled Mytraffic6 and, Voila! Its working fine
Of course it does. Whenever you have something misplaced, it's always an AFCAD conflict.
So now the question I have is, why is GSX reading the BGL files from Mytraffic all of a sudden and not the actual scenery BGL?
Because you might have moved the MyTraffic .BGLs set with an higher priority in your Scenery Library, which GSX respect, just like the sim itself.
How can I make GSX read from the third party scenery and not Mytraffic BGL's?
By being sure the proper .BGL has an higher priority of the MyTraffic one. Which is how we install our airports by default but, of course, if you reinstall MyTraffic OR you moved its folder manually, they might gain an higher priority, and GSX will use the ones with the highest priority, which is of course the correct choice.
HOWEVER, it's best if you prevent any conflict to begin with, and REMOVE every .BGL that comes with MyTraffic, if you have an add-on airport. That's because, due to bugs in how the AFCAD is read, some things (jetways and special effects) cannot be excluded properly, so many airports developers usually create many micro-exclude areas, in order to not have their own jetways disappear.
This will result in other .BGLs from the same airport to cause conflicts anyway, even if they are on a LOWER priority level! That's why, it's best to prevent the conflict entirely, by removing any duplicate AFCADs for an airport you have an add-on for. This will result in a better resource usage too, because it's a waste of memory (the sim keeps a list of ALL .BGLs in memory) and file processing too, since you are forcing the sim to scan and keep a list of a file which is not required.