When I start the 3D configurator it show me that the axes are set correctly but when I activate the jetway attache to 1 meter below and 1 meter to far into the plane as what I have set.
I think your main source of confusion is to assume that GSX has anything to do with jetways! It doesn't. Jetways are not affected by GSX in any way, they are not related to it at all, they worked (or not) before installing GSX, and installing GSX won't change anything to their operation. This is clearly explained on the manual, and has been explained many times on the forum. The ONLY "interaction" GSX has with jetways, is that it reads the AFCAD to know *where* they are, so it won't display front stairs and a passenger bus on gates with jetways.
This means, of course, that editing an airplane door in the GSX 3d configuration editor won't do anything to the jetway operation, the GSX editor ONLY creates a configuration that is meaningful to GSX vehicles and nothing else.
The FSX jetway only refers to the Exit coordinates as specified in the aircraft.cfg in its [Exits] section, and GSX won't affect or change that file at all so, if the jetway looks to be POSITIONED correctly (in the scenery) but it attach to the wrong place on the AIRPLANE, it's a problem of the airplane configuration.