Ok, if you look below, I have produced the exact hierarchy. It won’t import because of the multiple root. The bone thats right below root is the issue because its not in the root hierarchy. To fix it, I just parented it to the root and it imported in fine. That said, I did the same thing earlier, and it imported in, lol, a couple of times. Thats the thing sometimes, the engine is doing so much, it missed. It engine hick-up’d and let it in. I then parented it to the root using the child of bone constraint, it still wouldn’t import. The error was the same, multiple roots. I dont even know how you got it in to the engine, Ive got the same thing and it wont go. I did get it to import into the engine at first though. That has to be part of, or “the” issue.
The other thing is the blend shape animations. You want to have them in a seperate animation alone. I did get an error on the animation when I added it to another animation. It gave me animation sequence, like you have, but nothing moves. So, the blend shape animation is your other issue. You want to layer those animations inside the engine. Only do blend shape animations with blend shapes, don’t combine them with bones animations. For instance, the character is breathing if it’s a blend shape anim, you want breathing alone as an additive or an override animation. Like I said, I added the blend shape anim to a bone animation and it gave me a sequence, but nothing moved in the sequence. The blend shape anim inside the bone animation, and copying your hierarchy(with the bones outside the root) were the only ways I could get it to break. I even duplicated bones and it still imported with animations and no errors.
Last thing you could check is, go into pose mode, select the root bone, and try to try to move it. Every bone should move with the root. If every bone doesn’t move with the root, that’s your other issue. The solution for that is to go into edit mode and parent all those bones for the controllers, that aren’t under the root hierarchy, to the root. Remember, the child of constraint isn’t recognized in the engine.
Hope this finally leads to your fix. I can’t find any other issue to make it break. Otherwise, the only other thing is to re-rig. I think we have picked this all the way apart.
