I have an issue here where, no matter how many rigs I make, using "Humanoid" as the animation type results in this error. Just to be clear, the arms and legs are facing the opposite direction as if the orientation is correct. The head, chest and stomach are are placed as they should be. I will also provide a screenshot of the rig as it appears in Blender. (This issue appears in both fbx and blend format) The rig I've used is very simple. I made just enough bones to fill all of the slots humanoid rigs require. The only additional bone is the "root" bone underneath the model. The arms and legs are laid out completely straight. If anyone else has ever experienced this issue before and managed to solve it, please feel free to let me know. If needed, I will provide the model for testing.