Many thanks! I have corrected it and it runs. But oddly, at any keyframe it only finds one paramater for one actor. e.g.

I Load Andy. At frame 11, I set values for his "Chest", for Twist, Side-Side and Bend. When I run the script, it only finds "Twist". And not for the other two parameters.

It feels like Keyframes are attached to the Actor, but don't indicate all the Parameters which may have contributed to being a Keyframe for the Actor.

Hoping I am making sense. And more hopeful that I am missing something obvious.

Thank you.