Am using the most recent version, 3.7.5, but get the following in Couatl.log when progressive taxi is engaged:
[00:08:48.391] Slew mode True
[00:08:48.532] CREATE_OBJECT_FAILED in call AICreateSimulatedObject param #1 'FSDT_GSX_Pointer_ShowParking'
[00:08:48.532] Error: exception CREATE_OBJECT_FAILED in call AICreateSimulatedObject param #1 'FSDT_GSX_Pointer_ShowParking'
{'User Pos': (43.678921556023354, -79.59744404620132, 175.892 m, 2.46253 m, 226.8104340697175, 0.015284702181816101, 0.011344640515744686, -0.00018066207247419884, 2.5511759651184085, 1.0), 'Airport': 'CYYZ', 'Requested parking services to': 'Runway 23 Start'}
[00:08:48.563] GSX SimStop
[00:08:50.297] CREATE_OBJECT_FAILED in call AICreateSimulatedObject param #1 'FSDT_GSX_Pointer_ShowParking'
[00:08:50.297] Error: exception CREATE_OBJECT_FAILED in call AICreateSimulatedObject param #1 'FSDT_GSX_Pointer_ShowParking'
{'User Pos': (43.678921556023354, -79.59744404620132, 175.892 m, 2.46253 m, 226.8104340697175, 0.015284702181816101, 0.011344640515744686, -0.00018066207247419884, 2.5511759651184085, 1.0), 'Airport': 'CYYZ', 'Requested parking services to': 'Runway 23 Start'}
[00:08:52.063] CREATE_OBJECT_FAILED in call AICreateSimulatedObject param #1 'FSDT_GSX_Pointer_ShowParking'
[00:08:52.063] Error: exception CREATE_OBJECT_FAILED in call AICreateSimulatedObject param #1 'FSDT_GSX_Pointer_ShowParking'
{'User Pos': (43.678921556023354, -79.59744404620132, 175.892 m, 2.46253 m, 226.8104340697175, 0.015284702181816101, 0.011344640515744686, -0.00018066207247419884, 2.5511759651184085, 1.0), 'Airport': 'CYYZ', 'Requested parking services to': 'Runway 23 Start'}
Seems to be a missing SimObject.