I'm a long time user of SH3D.

- Yes it is dated (and very fast) - so what? The app is the important thing, the website works.

- If you need to find it, you will. I cannot recall failing to find download links (at least two of them on the home page)

- Mobile. Perhaps if you have a 21" screen on it!

ML? Not too sure about that here. Perhaps Ikea et al could run with that. I use it starting from reality. Perhaps hitching it up to a theodolite, EDM and other measuring tools would be more useful than a "what if I could read your mind and get it badly wrong" tool.