There’s an issue with v1.19 of GroundControl that can cause this. When the new groundcontrol.ini file is created, the section for propweightz in [Computed Settings] is not created.
The quick-and-dirty workaround is to add this line to groundcontrol.ini at the end of the [Computed Settings] section.
‘’’
propweightz = 1
‘’’
The groundcontrol.ini file will be in your home folder.