I am running into issues where hand models are deformed as soon as they are bound with the Hand Binder component. Aside from my own meshes, I'm seeing the same problems appearing with the included hand meshes: LoPoly_Rigged_Hand as well as GenericHand.
Comparing the original Low Poly Hand with the bound result in the included Prefab:
As you can see, the hands are elongated and narrowed.
Working in Unity 2021.2.19 with UltraLeap Tracking 5.6.0