Roberto - Thank you very much for posting pictures of your Cirkut. It looks to be in wonderful condition.

I hope it is alright with Clayton Tume, but I couldn't locate his wonderful website, so I used web.archive and found archived versions of his pages:
http://web.archive.org/web/*/http://...a_cameras.html
I haven't looked at all of the pages, but I did open this one:
http://web.archive.org/web/200804150...a_cameras.html
At the bottom of the page are a couple of links for the "Gears" program. I don't know if the link to download the actual program actually works, as I didn't try the download. In order to use the program, I believe you must have an exact measurement of the actual focal length of the lens, as measure on some sort of optical bench.

I didn't have any luck trying to recover the old Panorama mailinglist archives, which is very unfortunate, as there were many Cirkut related posts on that list. There is a lesson in the disappearance of that mailinglist. Whenever I see something online I consider really valuable information (such as anything related to Cirkuts), I always print out a paper copy and file it. i don't think there is any guarantee any internet forum or mailinglist will be online forever.

Len