Using CMU Graphics Lab Motion Capture Database I have been attempting to import CMU motion capture into Unity through Blender.  I was specifically using actor number 127, action number 3: Run.  I was downloading asf/amc file format.  I then used amc2bvh to convert it to bvh. (I have also tried the native AMC importer, but it doesn't seem to to work as well) Once it is imported, I save the blend file and import it into Unity.  I change the avatar to be a humanoid avatar and leave the defaults.  This is the result. 


If I add bone rotation constraints to the thighs and limit the rotation on the Z-axis, then that seems to resolve the problem with this particular one.  I would like to fix this a better way that way I can use the rolling animation in such in my game.  If anyone has any idea how to solve this, it would be much appreciated.
I suggest using bvh files from this library
CMU-BVH

On youtube, check out Benjycook Blender MoCap Addon Tutorial, which uses the same library.
BenjyCook