Nice. Yes, it is a very special lens...I have done some research into it. These zooms were entirely handbuilt by Technovision using parts from a 20-100. It's sometimes a bit weird, crazy flares and all that, but it makes really pretty, organic images.
Mine vignettes heavily until about 25 mm. Are you able to shoot at 18mm with it? Is Duclos able to help with that?