One of the slides at that URL has Dave Yost's Clint Eastwood fillColor displayed in it. :-)
I think you can run it as long as you have a PPC machine. Perhaps one of the Mac OS emulators that emulates the PPC could do it, too, if you had the ROM files.
In case you're not familiar with ROM files, the old Mac OS, before OSX, was not really an operating system in the usual sense; it was really a large subroutine library, the bulk of which was burned into ROMs in Apple hardware. Emulators for the old Mac OS need to have working copies of the contents of those ROMs in order to run the Mac OS. ROM files are a little bit inconvenient to come by unless you have an old working Mac and a tool for copying the ROMs.
Way back in 2004 I proposed an open-source project to build a new SK8-like environment, and even got buy-in from some of the original developers and users of SK8. Then I got terribly sick and didn't work on anything at all for a couple of years. When I finally began to work again, it was with a lot less energy and ambition than I'd had before.
If you want to build it you'll need a working copy of MCL and a PPC mac. The requirements may be slightly narrower than that. SK8 had some low-level bits that might rely on some details of the Mac System version or hardware. I don't rememberenough of the details anymore, but you might need to try a few different PPC models and system versions. System 7 or 8 is probably a decent bet, as is any mac hardware that was shipped with it.
