Hi Kenny,
Thanks for the kind words…

We're talking XS8 here What's it gonna take to get an mlan functioning ,FireWire rig running?

My first instinct is to say, a Time Machine. Mainly, because the playing field is filled with several booby traps because of several operating system changes.

You will want a Mac that has FW, or at least Thunderbolt hardware connectors that can be made backward compatible with FireWire.
Any of the more recent Macintosh computers cannot be adapted back to use FW (afaik).

Now the XS goes all the way back to mLAN (which allowed networking). It also was compatible with the newer FW driver (peer-to-peer), like the XF. I would abandon all hope of returning to mLAN (Motif ES circa 2003), and if you are up for the adventure, make an effort to get the Yamaha Steinberg FW Driver to run on a dedicated old system computer.

Necessary Disclaimer:
“Friends don’t let friends use MS-DOS” - That was the old saying, back-in-the-day before Windows. Well, I would be remiss if I didn’t try to talk you into a MONTAGE and the current 32-bus audio out, 6-bus audio return system via USB. Not only are all the Motif XS sounds compatible with the new MONTAGE engine but you get more than double the processing power, double the number of audio bus outputs, about eight to ten times the synthesizer. (Plus it can run on the majority of present day computers and computer OS — excusing Apple’s latest chipset change, etc., which is the first major hiccup since the days of XS (mid-2000s when Apple had its last major change).

You may have other nostalgic reasons for this time travel adventure… but you have been warned. If you have a choice - get a MONTAGE.

You maybe able to succeed -restoring old systems… If you avoid newer Macs (nothing newer than first generation Thunderbolt) and if you can find a DAW version that can run on that old OS. And that’s another thing…
Your path is going to be full of non-compliance, 32-bit versus 64-bit plug-in nightmares, and the feeling you are out on a tree limb without help.
Everything is 64-bit now, some stuff back in 2007 were 32-bit only. Fortunately, the XS Editors are 64-bit. You may not be so lucky with everything.

I successfully ran a Motif XS/XF w/FW through to mid 2019… I was able to adapt the Thunderbolt to 9-pin FW and the 9-pin FW to 6-pin FW. Everything worked like champ, I had no reason to extend it beyond that and was relieved I did not have to try… the adapter chain looked scary enough… when I got a newer Mac with USB-C only, I retired FW altogether. I really don’t think USB-C can be adapted back to FW (6-pin) but this is not my forte (hacking ancient computer OS’s).

As you may know, my forte is the synthesizers. When it comes to which version of Cubase to use… again, you’d do best to consult Steinberg. Non-compliance doesn’t always mean it will not work. But it does kind of hint that the difference between what it needed when new and what is on offer now are so far apart, that no one is testing it any more (so your mileage will vary). They would know about workarounds (if they exist) or they could just tell you to forget about it!

All of the nice things that made the integration smooth and enjoyable, may no longer work as originally intended or may no longer exist.
What is the ultimate goal with this project?
While Yamaha’s mLAN/FW feature is apart of the past, it evolved into the robust audio/MIDI system found in the current MONTAGE.
If your goal was to go back to the mLAN (true networking) you will need to get an old Mac (as the changes made. to Audio capability in Macs was changed circa mid-2000s. They no longer supported true networking of Audio and MIDI devices… all connections with Macs required peer-to-peer connectivity.