Thanks
@MBongo for making the thread, I was finally able to get past the registration and login duration woes here, so now I'm finally able to participate here, as well. (Just not from native Mac OS, as the website causes the browser, and even OS, to crash on Classilla, despite Crypto Ancienne taking care of TLS. I never had such an issue with any other website I have ever visited on the browser, not even GitHub or MacRumors).
For clarification (just to be sure there's no risk of misunderstanding from any side), the sole author of the
project itself is
@Rairii, to whom we all owe for this phenomenal outcome. And to
@elliotnunn for his Mac mini G4 compatibility patches / scripts and patching tools, plus Mac OS 9 Lives!'s various contributors like "darthnvader" (ATI driver patches), "iMic" and lots more people.
I am merely a messenger who tried to put together a summary of everything for everyone else to also follow along.

And who applied
@elliotnunn's Mac mini patches to
@Rairii's ROMs to test it all on my 1.5GHz G4 mini and attached the new mini ROM on my post on "Mac OS 9 Lives!" for other mini owners to join in without having to do the patching on their own, if they prefer. Nonetheless, I'm glad everyone seems to be enjoying all of it: the project, the summary and the milestones that were reached!
My mini is currently my only PowerMac currently able of booting into Mac OS (sadly): I also have a DLSD G4, but that's the last G4 Mac that we have yet to get booting Mac OS on, somehow... (And even if we do, the GPU will have no acceleration, short of someone making/porting/patching in Mobility Radeon 9700 drivers.)
@eharmon I actually ended up booting all these systems off FireWire without any FireWire-related extensions, even System 7.5. I was and still am surprised that FireWire and USB just work like that, thanks to those ROMs!
I'm also glad to know a later version of the System Profiler fixed things! That's exactly what I was hoping for, for the various things that have yet to work right.
Did you also get sound to work, by the way? Like, at all? How were you able to do it, if so? Bringing in a later version of Apple's sound extension(s)?
Too bad about networking and graphics, though. I'm sure we can manage
something to get the mini's ATI Radeon 9250 going if we keep at it, if nothing else... But I have no idea what prospects there could be of getting Ethernet working.