You mean "vabb Thai creations addons doesn't work with GSX", not the opposite...
From your message, it seems that scenery has a faulty AFCAD, most likely unconnected nodes, orphaned nodes, overlapping nodes, missing links, unreachable paths, etc.
If you open the scenery AFCAD with an editor like AFX or ADE, you'll likely find some errors with the "Fault Finder" option these tools have, so you better report them to the developers of the scenery, because such errors will likely cause other issues with AI too, not just GSX.
