Hello RogerD

A warm welcome to these forums.

I think I understand the issue here.
The Imperial is based on a Ransomes' design - which had a key slot
on the other side of the spindle. The Imperial does not have this.

A quick shock is all that should be needed to unlock the LH thread.
A soft piece of wood accompanied by a mallet blow (clockwise) should
release the thread.

Lack of drive will be a differential gear problem.

Hope this helps.
--------------------
Jack

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