Yes, I’ve seen that but it doesn’t help, because it doesn’t show how to use the “VST Transit Join” plugin at the “far” end … i.e., in the the video, PT is used to “record into” VST Transit Join (AAX) and at the far end the iPAD app is used. In my case, I’m using VST Transit built into Cubase 10.5, and at the far end is Logic on OS X, using the “VST Transit Join” plugin.
“VST Transit Join” is also an AU. The installation, loading of the “VST Transit Join” (I think the AU plugin shows up as an “instrument” in Logic terminology), login and connection to my Cubase project all appear to have worked from Logic, and playback was possible. What I’ve been told by my collaborator is that it was not possible to “record into” the VSTi (as done from PT in the tutorial video above) and that drag-and-drop of a recorded track from Logic into the “VST Transit Join” VSTi also didn’t work. One other curiosity was that when a “region” was created in Logic, I saw it appear in Cubase as a folder track … so the funtionality appears to be there and working, but just not how we expected.
At that point with any other product I would “RTFM” to check what the expected behaviour should be, and to verify that we were attempting to use it properly. Hence the question … is there no user guide for the VST Transit Join, specifically, how to use the VST3/AU/AAX plugin in other hosts? (…and yes, I do see the word “beta” there 
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