Hi @LukeLER
would you please update StepUp installing the StepUp WB through FreeCAD Tools Addons menu?
That will let use StepUp as a FreeCAD workbench and let you know if your release is up to date.
After installing StepUp as FC WB and close and relaunch FC, you will be able to directly open a kicad board in FreeCAD.
you may also find this useful
kicad-stepup-cheatsheet
Please let me know if this is solving your issue …
Maurice