Thank you all for comments and advices,
and not the least, warnings on the behavior of wet FB paper in large sizes. Saved me from hospitals closed area following struggles with sqaremeters of wet paper entangling me like a Python.
I appreciate your infomation on your experiences with different methods of rolling, scrolling, swamping and others methods of development and practical advices on the building of devices. And your references, hereamong to a 100 years old instruction, fascinating thought.
So, to play it save for a beginning, I may start with scrolling in halftube trenches. Also, to take a beginners route, begin with smaller sizes to get the feeling of it, as well as learn of differences, if any, in shadow and highlight behavior between submerges tray development and more or less airexposed development. And then go on with the scale up.
I look very much forward to this proces, and I have certainly written your advices and recommendations behind my ear, once again thank you very much.