Awesome stuff, here. One thing that's always struck me as interesting is how much more frank Japanese developer interviews are than English ones for western audiences. For instance, there's an interview with Oshima about Sonic CD where the official English translation leaves out a lot of detail and polishes it to remove any negativity. It's sorta like the difference of the behind-the-scenes stuff between Phantom Menace and Last Jedi, wherein the former it's quite blunt about all of the issues, and the latter is essentially whitewashed promotional material. Anyhow: Hmm, 5 zones. I'm going to guess that they were Hidden Palace, Sand Shower, the winter zone, Wood, and Genocide/Cyber City. That's 5 right there. Ah, if only we had the development materials of them. If we got Tom Payne's disks of early dev material, I'd hope those zones might be floating around somewhere.