Kicad StepUp New exporter for 3D MCAD (feedbacks are welcome) - 3D Models - KiCad.info Forums
FreeCAD: Deleting holes and fillets from shapes in STEP files - XSim
step-imported-into-freecad - DreamLight.com
FreeCAD tutorial: How to test the assembly module [updated]
GitHub - FreeCAD/FreeCAD-library: A library of Parts for FreeCAD. WARNING - This library is huge. It might take a long time to download and make the addons manager unresponsive for many minutes.
How to modify a STEP file in DesignSpark Mechanical (tutorial) - Repper's Delight