You need to learn python. At the bottom of the manual it has the instructions on how to do it.
Basically you set your nose position at the first stop bar, then record where each of the forward stop markers are using the ruler that is provided when setting the stop marker. You then use the aircraft codes to then assign what distance they are at.
This is my code for CYXU:
msfs_mode = 1
@AlternativeStopPositions
def customOffset5(aircraftData):
table = {
# 0, 2.1, 4, 7.4, 9.8 (these are where I put as a note what all the measurements are)
0: 0,
300: 9.8,
319: 2.1,
320: 4,
321: 7.4,
}
table737 = {
"B737": 2.1,
"B738": 4,
"B739": 7.4,
"B38M": 4,
}
if aircraftData.idMajor == 737:
return Distance.fromMeters( table737.get(aircraftData.icaoTypeDesignator, 0) )
else:
return Distance.fromMeters( table.get(aircraftData.idMajor, 0) )
parkings = {
GATE : {
None : (),
"5A" : (CustomizedName("DCD|Gate 5"), customOffset5),
}
}