BlendState in Animation Layer freezing Unity (Mecanim)

Greetings. I’m running into an odd freeze in Unity.

I’m creating a blend system that will allow our character to use nine animations set up in a grid to allow him to track targets with his upper body. I’m using the “Wave” layer example in the Mecanim as a basis for my setup.

I’ve created an override animation layer with a skeleton mask, and have put an empty animation state in it and called it “EmptyState”. This state has a transition going into a Blend Tree, with a Boolean value on it that trigger when true.

Inside that blend tree , there are three other blend trees. The sub trees are blended using a Float “Horizontal” value going from -1 to 1. The three sub trees have three motion fields, blending using the “Vertical” float value.

Basically, the first tree blends between a left, center, and right position. The sub trees blend between an upper, center, and lower position. Everything works fine when I check things inside the tree.

Now to the freeze. After placing all the animations into the blend tree, I go back to the root of the animation layer and select the transition going from the empty state to the blend tree. Everything looks fine. Then I select the transition going from the blend tree to the empty state, and Unity freezes.

I can see this error in the lower left before it finally crashes a minute or two later:
“State preview.EmptyState has no motion”

Help?

Exact same problem here, any solution?

This happened to me when the animations were part of the same fbx file cut up into different clips. When I split the clips into their own fbx files, it didn’t crash anymore.