@MojoGames I have also been using arms created from FPSMeshTool and a humanoid model as suggested in the tutorial videos. If you use the "Demo" controller instead of the "FirstPersonDemo" controller you will get your animations back since it does use that rigging system. With all other body components disabled only the arms animate. You do have to modify things like crouch and such in the controller though, so I recommend copying the controller and modifying it to your needs.
If the first person arms in the demo seen used a humanoid system to start rather than one unique to Nolan these sort of modified humanoid meshes would just work.