Won't run on 64 bit only OSes. OSes with 32 bit multilib runtimes will do fine.

Worth pointing out that those are becoming increasingly uncommon, with Apple already having dropped it, and Microsoft dropping it from Windows 11 (EDIT: okay, I misremembered: Microsoft is dropping support for 32 bit installs, not WoW64). For the moment, 32 bit x86 multilib is still common on Linux, but I wouldn't be surprised to see it start to disappear in the next 5-10 years.

So this isn't an immediate problem for most people not running MacOS, but will eventually be a pretty big problem in the next decade for this project.

Yeah that's still an unsolved issue.

Now I mostly work on macOS for mobile apps development, and sadly can't run Red.

64-bit is high on our list, but also a huge task, so needs a large block of time where other things won't get done. We have some big features we're pushing on now, and will update our roadmap accordingly.