Thanks for the file and for using iCloud.
There are two things that I would change.
Delete all the Keyframes of the Joints. With this, the Function, Convert Layer to Keyframes.
The second one is not crucial for the keyframes but for the usability of the Motion clips (on the long run). I would not place the object/skin inside of this.
The Motion system works with Hierarchy. It doesn’t search for parts; it just takes what it gets. If that doesn’t fit, no show (instead: chaos!), or you alter each clip manually.
With that, you might limit your usability, or at least the effectiveness of your certainly growing library.
I saw suggestions to take the top joint as a Motion clip starting point, but since that might not always be the case, I think that a Null on top is the more common way. If this null is applied later on, it needs to be done manually. While the Null sitting on positions 0, 0, 0, and zero rotation while the scale is set to one for all. Never ever use the Group shortcut for any animation.
Here is your file back; use the Convert to Keyframes again, and it should work just fine.
Enjoy your weekend