Below you may find the content of gsx.cfg for Carenado's Fokker F50, including embedded stairs.
Peter
[aircraft]
nosegear = 8.79
refueling = 1
battery = 1
iscargo = 0
trafficcones = 1
preferredexit = 0
wingrootpos = 1.20 -0.59 0.30
wingtippos = 13.73 -0.66 0.30
fuelpos = 4.89 -0.40 -0.20
waterpos = 0.00 0.00 0.00
lavatorypos = 0.84 -9.91 -1.50
engine1pos = -3.52 -0.30 -0.51
engine2pos = 3.52 -0.30 -0.51
engine3pos = 0.00 0.00 0.00
engine4pos = 0.00 0.00 0.00
[exit1]
pos = -1.09 5.99 -2.19 -0.80
code = 1
name = Passenger door
embeddedStair = -1.12 5.94 -2.11 -2.48 5.94 -3.16
[exit2]
remove = 1
[exit3]
remove = 1
[exit4]
remove = 1
[service1]
pos = -1.00 -7.08 -2.16 -7.30
code = 2
name = Service door
embeddedStair = 0
[service2]
remove = 1
[cargo1]
pos = 0.98 5.97 -2.27 -0.10
code = 2
name = Forward cargo door
embeddedStair = 0
uldcode = BELT
[cargo2]
pos = 1.02 -7.11 -2.14 9.10
code = 2
name = Rear cargo door
embeddedStair = -1.59 5.98 -2.24 -2.20 5.97 -2.85
uldcode = BELT
[cargomain]
remove = 1