Okay, after alot of time researching, downloading aircrafts (freeware), buying (airbus from steam edition [which I don't recommend anyone to buy] and PMDG [worth every penny]), and testing.....
It seems GSX works 100% only with payware PMDG in Steam Edition.
All freeware of aircrafts made for FSX are amazing but my guess is I will have to try to sync ground services to doors + cargo, etc... which is pointless because screens go black at anytime.
Instead I bought PMDG 777, I can control all doors + cargo doors and all GSX services line up perfectly, and the best part is that I can actually last 20 minutes "boarding" and getting all ground services and panel screens will remain active.
GSX its worth every penny for anyone that wants to make their simulator more realistic.
One question for the devs, I noticed that the luggage carts (2 of them, 1 for each cargo door) just come by the plane once to drop all cargo, is there a way to make them come back 3 or 4 more times?
Thanks.