Thanks to a reaction on this project that I got, I got some new experiments in the pipeline. The major one is implementing alpha transparency for the Okuda elements so that the interface can be used as an overlay for AR for example.
Yesterday it looked like implementing proper alpha masks was next to impossible because of the structure of the elements, the editor and the fact that the code is quite old now.
But with some experimentation, I think I have found a way to implement it in a way where the data structure remains the same, events are kept, browser compatibility is ensures and where I do not have to overhaul my development environment.
(it basically means that I have to write a replacement function hack for "obsolete" browsers)