Part of animation shows in preview, but not in game

I am experimenting with animation using Blender's IK. Since it's using IK, I'm exporting the results as a FBX file to Unity instead of using the .blend file directly, since Unity seems to have issues with the IK stuff.

The imported FBX file in Unity shows properly in the inspector preview, however when I use it in a scene, the feet aren't animating as expected (see screenshot). I have no idea why only the feet would do this, especially when they animate properly in the preview. Any ideas?

Thanks!

 

More info... I figured out that if I duplicate the animation that's embedded in the FBX, the preview of the embedded one is incorrect the same as how it plays in the game. Something is getting messed up in translation between the embedded data and actually using it.

 

Another update... changing the rig type to "Generic" instead of "Humanoid" seems to fix the issue. However, I'm not familiar enough with the purpose of the "Humanoid" setting to know if this is necessary to use for some other reason.

 

Ok, Humanoid is needed for UMA, apparently, so I changed it back. And now the animation is playing properly in the game. WTF???