Since GSX has been released in 2012, it never worked with any airplane, unless a proper configuration is made for it. By using the included airplane configuration editor, you can customize every airplane, if it's not already included with GSX and about this one, of course, being released just today, on a Sunday to begin with, you cannot expect it would be already included.
The issue of GSX not detecting doors, is due to the fact the airplane surely use non-standard variables to control its doors. Which is why, the GSX airplane configuration editor give you a choice between either writing a custom XML expression, which will contain the name of the custom L: variable used by this plane, or you can tell GSX to IGNORE the door's status altogether.
This is of course fully explained in the GSX manual, at Page 47
So, you can either try making a configuration yourself, or wait for us to do one which will be included in GSX.
About the boarding time with passengers, this is controlled by the "Passenger Density" slider, which is explained at Page 26 of the GSX manual.