Even if an airplane model is the same, different developers might use entirely different reference points for their models, so measures will almost always never match.
Creating an airplane configuration for the doors locations is VERY easy using the GSX editor, what MIGHT be difficult is figuring out custom XML variables for airplane that don't use standard doors variables. That's why I've said that we might have to add a QW146 configuration ourselves, like we DID for the Avro models, because QW USUALLY use some custom variables for the doors.
But JF, USUALLY, makes simpler models using standard door variables, that are way easier to figure it out, you have only 4 choices to try at the most, so I don't see having to create a special GSX configuration ourselves for the JF model to be as useful as it would be for the QW model, because anyone should be able to create one, using the included airplane configuration editor in GSX.
Again, assuming this JF model is made using only standard door variables. If it's not, we would like to know about it (I didn't know that JF *had* a 146 model on offer, it's impossible for us to support our stuff and be aware of everything that's out there...), so we might consider adding it ourselves and IN THE MEANTIME, GSX can be configured to IGNORE the door's status, which is the option that will always work in any case so, there's absolutely nothing that prevents GSX to be used with any airplane out there, even one that is not natively supported.