Thank you for posting the results of your hard work on this project. I have been collecting the energy required to do my own "Man Ray" type of films. Abstract work. I have the 16mm camera (spring driven), silent projector and negative film stock. I would love to use a sealed development tank, but for me I think I will have to devise a really simple solution, else I might lose interest.
I haven't built this yet, but I am considering making a "Ferris Wheel" or "Water Wheel" contraption where the film is wrapped on a much larger cylinder. ie 24" diameter. I would spin the wheel by hand over a small tank of chemicals and then I would simply move the wheel to the next tray/station at the appropriate time . . . or better yet, I could just swap in a different tank of chemistry at the appropriate time. All the development steps would need to be accomplished in complete darkness, of course. I'm trying to imagine any pitfalls in this concept.