I bought some animations through the Mixamo Animation Store, they worked fine in the preview but when I went to add them to my animator they wouldn't work. I went to look at them and there was no preview, so I dragged the model I used for the preview into the preview section, but it wouldn't take. So I dragged a different model, one that is not set up as a humanoid but as a generic, and the model went into the preview, but it wouldn't animate, probably because the model is not set up for that...
Mixamo Animation Store trouble with animations
Mixamo Animation Store trouble with animations