Why this model is working bad with BoneIKController, anothor is working good，help

Questions
1

1.Working bad: demo, source
This model was export by mixamo ybot used blender and Blender2Babylon-6.3 followed Mixamo - Babylon.js Documentation.

2.working good: https://www.babylonjs-playground.com/#4HTBYP#2
This is a question anser, my demo based it.

2

Hello,

Could you reproduce the issue in the playground so it is easier to see the code ?

Also is it related to export or the code ?

Thanks,

3

Yes.
https://www.babylonjs-playground.com/#JVZFN1

4

Pinging @adam who created the IKcontroller