How to operate a Multispeed shutter?

Another question for the oddballs department

I just got another nice camera with a Multispeed shuttered lens.

Of course, the T, B, and I settings are easy to figure out; but I am lost about the A, B, C, D scale and its connection to the 1, 2, 3, 4, 5 scale. The little crank on top of the shutter which rotates the numbered scale, appears to wind up a spring to different tensions and has a little lock button for some unknown purpose.
To make matters worse, someone had attempted a "repair" to lens and shutter in the past (looks like a pair of large screwdrivers had been used instead of proper lens spanners). So aside from a horrible looking lens casing, the ring with the 1-5 numbers sat rather loose, allowing the gears of the crank to slip, thereby trowing the setting marks off.

Any suggestions?

http://www.cameraeccentric.com/html/info/interlens/interlens.html pages 14 and 15.

I've never seen one, and you've got my baffled in my armchair, but this might be a start. Good luck.

Thanks for the info.

I had already consulted that particular book, but it only covers a later version of the Multispeed shutter. The book shows a decisively more tamed down design. The earlier Multispeed's have this gritty industrial look to them, which is way more cool looking . I've made a quick little grabshot (attached shot) of the shutter to illustrate my "problems".

Cheers,
Chris