Can fellow readers make a short pitch regarding why someone who is not familiar with Oberon would be interested in it today (other than historical curiosity)?
I don't know of any other system that accomplishes as much with the same amount of code lines. It includes not just a kernel, but also a compiler, a dynamic linker, an editor, and an unusual blend of a desktop and command line.
It's not something you'd want to use today, but it's certainly worth studying. It's a wonderful lesson in keeping complex systems as simple as possible.
AFAIK there is no way to follow instructions from somewhere that results in an actual working system. I think there's something experimental that works on top of a Smalltalk system, but that it's not able to work independently of that. I also don't remember all source code being available.
Oberon is able to run on actual hardware and works in various emulators.
I do love the research they did for STEPS though, it's unfortunate it didn't result into an actual release.
Indeed, Michael Franz's work was certainly impressive. It's unfortunate that the code readability of those parts didn't quite match up to the rest of the system.
It features an alternative way of object-oriented design with focus on messaging and message inheritance (instead of the usual dynamic dispatch and class hierarchies). And the Gadgets framework is also pretty interesting and likely worth to be reused in current systems.
It's not something you'd want to use today, but it's certainly worth studying. It's a wonderful lesson in keeping complex systems as simple as possible.