I had no problem with Sierra …And why wouldn't it just work? It's true you never know with Apple, but according to the support site (it's an Arris product and discontinued too...) version 8.x only supports up to 10.10 so if it supports 10.11 then it's likely that it would work in 10.12 barring specific evidence otherwise.
… in High Sierra, this happens (see attached images).What happened when you tried it?
I've heard of High Sierra breaking other apps. This one could be a casualty as well. Since the error is related to the Host application, I would check the path to it in the app package to make sure it's not different in High Sierra.in High Sierra, this happens (see attached images).
You’re probably right about Apple File System being the culprit … Mini vMac won’t boot either … :-(Did you check that the filesystem on the startup drive is HFS+?
I believe that if the main drive is an SSD, HS will automatically convert it to APFS, and I think that's part of what's breaking stuff (most older software is probably hardcoded for HFS+, and breaks when the filesystem is something else).
Also, I don't know if it's starting yet, but I think Apple is going to start deprecating 32-bit programs, either in 10.14, or in some update for 10.13.
Nevertheless, since Sierra has updates for ~1.5 years more, and this software apparently works okay on it, you can fall back to that and probably still be relatively safe if HS doesn't work out.