Hello Dan,,
I have read the description of your problem and I would love to help. I have experience developing and troubleshooting Unity projects as I have worked with the engine for 2+ years. You can view some of my small projects on my website lpgamedev.com.
From what I understood in the bug description, the problem lies in either the animation itself or the responsiveness to input.
Would love to chat about the problem some more and figure out a solution.
Cheers,
Mykyta