You don't need any custom GSX profile for the 737 NGXu. With the current update, which has been available online since Nov. 10th, GSX supports the new 737 out of the box, with no further customization required.
In fact, it's best if you remove every custom file you might have been made/downloaded, because custom profiles always take precedence over the internal ones so, if that profile is not made correctly, it might not work correctly.
About jetways, the ones in your screenshot are not from GSX, they look like FlyTampa jetways at EHAM, and nothing in GSX would change or affect how they work, they are totally unrelated to it.