I have released the first version of FreeCAD/Croquet (Project that I'm working on).
You can get it here which is the version loaded into Cobalt. After downloading it, launch Cobalt and drag KayefFreeCAD out from the parts bin and it should load.
If you already have a Croquet image then just use the Monticello package. Please follow the instructions in this link on how to install the package.
Once you get that running, follow this link for tutorials on how to use it. Currently, you can create 3D solids and also load sample assemblies. Watch some of these videos too if you have the time.