The problem doesn't have anything to do with GSX or any of our products. FSDT sceneries and GSX creates jetways on their own ( SODE only animates jetways that has been already created by GSX ) objects on their own, so you will never see Red X as a result of a problem with them.
Red X comes from SODE when you have a 3rd party scenery that uses SODE objects is trying to call them ( because there's a SODE XML file for it in the Programdata\12bpilot\XML folder ), but the objects are not there anymore, likely because the scenery has been removed manually, or the scenery uninstaller is faulty and doesn't remove those extra SODE files.