Why won't my simple rig not animate?

Help and Feedback Game Design Support
1

I am trying to animate some arms I made recently for an FPS game. I’ve used the rig editor, didn’t understand it, so I added Motor6D’s manually.

Explorer:
image

Animator:
https://gyazo.com/985af67f41f4c44b4b636e155d3cccc5

What am I doing wrong? The Motor6Ds are configured correctly.
The humanoid root part is the primary part of the Arms model.