IT WORKED!!
Thanks for your suggestions. I shot some Goof Off into the bottom and sides of the mirror slots and on the shutter blades. It took several applications, cocking and winding many, many times. Then it worked a few times, but hung up again. I kept it in an unheated porch overnight to dry thoroughly, and now it works like a charm. I fired it 100 times at various speeds without a hitch.
Now, let's get some Zeiss glass. Anybody got somes spares?