http://deathball.net/notpron/
I can't figure it out yet, but there are 81 levels.
Odd game
No, I'd say it's quite different from Myst. Try looking on their forums; each different level has its own specific hint thread. I only got up to level 12 or so, but it was getting to be too time-consuming, and I couldn't figure out any of them without looking at the hints. Besides, considering there's no plot, it didn't seem worth it.