Mixamo Animation Retargeting

Hey there. I bought this time ago, not used it till now.
Its not working for me, this is what i am doing:

1- I make my character in fuse standalone, upoload to mixamo, autorig it and download the model in Tpose.
2- In Unreal, i retarget the character to the mannequin, just like in the video.
3- Now, i want to use this model with the locomotion system V3; i just change the mesh like they make in the video, and nothing happens.
The mannequin was playing an animation, and when i exchange it with my new retargeted mixamo character… then it stands in Tpose…