I believe I've found a bug with generic rigs and additive layers.
If an additive layer is selected for editing in the clip editor and "Auto Key" is set to "Generate", often when switching animations or exporting, one or more scale keyframes (and sometimes a rotation keyframe) is added, causing the final animation to be modified and exported incorrectly.
Scale keyframes should not be added to the additive layer of animations when switching animations or exporting aimations on a generic rig.
Steps to reproduce
1. Create a uMotion project and configure a generic rig
2. Set "Auto Key" to "Generate"
3. Import an animation or add some keyframes to the Base Layer
4. Create an additive layer and place some keys for bones in the rig
5. Export animations (or, sometimes just changing the selected animation for editing will do also work)
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