Ok, an update. There was an update available for GSX (3.4.6 to 3.4.7), so I installed it. After that I was able to exclude 3rdparty jetways for CYVR. But they are ugly!
With jetways disabled, there are no faulty dead-end jetways, and they work. But they are ugly (solid with the HSBC logo), not as nice as the other ones with the Vancouver logo on.
If I enable them, I get the nicer ones with the YVR logo, but also the faulty dead-end ones. And they doesn't seem to work.
Is there a way I can get the nice looking ones, and only those (and get them working of course)?
Many thanks!