Before you mention that a) S1 Artist doesn't support 3rd party plugins or b) Mobius is only 32 bit I will say upfront that a) I have S1 2 Producer which does support 3rd party plugins, b) Mobius for Mac now runs in 64 bit (and I already tried starting S1 in 32bit mode) and c) the darn thing was working for a week or two and being used in professional setting. IT WAS AWESOME! - such a problem solver.
So, as mentioned it was loading in as an effect plugin and I was able to route buses, set MIDI bindings... everything. Now, after two weeks, I can not find it in my list of effects. When I started S1 and opened a template that had Mobius as an effect insert I would see S1 adding it via the notification box during startup. In the assigned effect channel, however, it would show red and put-up a notification that Mobius could not be found. When I looked in the overall effects list on the right it was not there.
I checked my HD audio plugin folder where all other AU, VST, etc, are stored and I DO SEE both the AU along with all others in the Components folder and the VST in its folder. I don't know why that is the only one not loading in when S1 starts up and goes thorough the VST support.