This semi proves my point that something in the latest update, as well as something that's related to GSX and being pushed to the other installers for FSDT products through a live update in the installer is causing the issue for us.
Well, of course it's related to the update but, don't confuse cause with effect. If you have a crash with the "bglmanx.dll" error, the message is related to the fact it has been updated, but that doesn't mean there's anything wrong with it.
That message is a generic message that sometimes FSX throws out whenever you just trust a new module that has been updated AND the module has a digital signature and it couldn't load it for any reason. I sometimes got this from modules from every developers, but it always disappear after a restart or another try, so it's possible it might just a bug of the FSX re-trust routine.
But not many updates their modules as often as we do, and this is also an issue with some antivirus, that use very questionable heuristics to block/allow a software based on a "reputation" score, which is clearly wrong, because a software updated very often will never get a chance to build any reputation, and by doing so, the antivirus ignore both the fact the module is digitally signed (antivirus vendors suggest to do this, as a best practice to prevent false-positives) with an authenticode digital sign AND it has another digital signature, called Software Taggant, which is specifically designed to prevent false-positive in the first place.
P3D doesn't have the "trust" routine anymore and, guess what, we don't have any reports about the supposedly "bad bglmanx.dll" from P3D users.
So yes, the problem is related to the update, but it's not CAUSED by it. As I've said in all other threads, if you still have this, please contact me in private to arrange a Teamviewer session, because it's the only way I could see what's the problem in your case, since we are still unable to reproduce it in any way.