There are few very annoying bugs.
We are using UMotion to edit animations recorded using Optitrack Motive software (mostly <10s, 30fps), and during postprocessing in UMotion, very often keys just stop generating despite having Auto Key set to Generate.
Also, when that happens, enabling IK Pinning stops working - there is no message box, and selected object just snaps to what I think is a 0 position.
The one thing that fixes it for sure is UMotion restart.
The last very annoying thing is performance drop after a longer session of editing. Animations get so choppy that it's almost impossible to edit them. UMotion restart doesn't fix this - Unity restart is needed.
There are no error messages in console when those bugs appear.
I hope You'll resolve those issues soon.
EDIT: I've added a video presenting IK Pinning issue: Video presenting bug
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