Hi there @damoski
To my understanding the Swing 50 to 72 percentage amount is related to the Arp Tempo. If you use "SYNC" the Arp Tempo is synced to the Host Tempo, it will then follow your DAW Tempo. If you disengaged "SYNC" then the Arp Tempo will synced to any value that you manually enter in the "Tempo" box.
So let's say you have your DAW Tempo set to 120 BPM, if you play an Arp sequence from ANA 2 with "SYNC" engaged it will follow the Host BPM. With "SYNC" on and the "SWING" knob turn down to 50% there's no swing happening. Now if you disengage the "SYNC" button and manually set the "TEMPO" value to 120 inside ANA 2 and keep the same 50% setting for the "SWING" it will result in the same playback & no swing being applied to the Arp.
Same goes for the Max 72% "Swing" value of course, whether you use the manual "Tempo" value set at 120 or engage the "SYNC" button with your DAW Tempo set at 120 BPM, you'll get the same Arp playback if the "Swing" knob is turned full right at the max 72% value.
Now to be honest, I also find those 50% & 72% values confusing, for me it means more "No Swing" or "Max Swing" amount, maybe @phil_johnston could explain more about this.
What I was trying to explain in my previous post is that the swing or groove that you can also apply in Ableton is not related to the Arp swing amount value inside ANA 2 and if someone was to apply a groove on the Midi clip triggering ANA 2's Arp, it will first affect the Midi events before reaching the Arp module and therefore result in a playback offset/delay. While this could be used to get something more creative, the only way to stay in sync when you want/need to apply Ableton groove/swing to your tracks would be to render the audio out of ANA 2 and then apply Ableton's groove to the sequence. But again, just to mention that Ableton's groove/swing and ANA 2 Arp swing are not related, only the host tempo is taken into account when "Sync" is engaged inside ANA 2.