Quick summary: Air Manager does not seem to be connecting to X-plane at all.
X-plane 11, OS X 13.0.1. A few days ago things were working fine on another Mac, but I'm getting up and running on a new machine… I did install the Air Manager plugin as per the manual (ie. Resources/Plugins/Air Plugin/64/mac.xpl), but I don't think it's working. How can I fix this?