Custom Actions: Zapier Catch Hook Not Working

I have a different but likely related issue: my test hook isn’t being recognized at all by Zapier. I posted as a comment in the announcement thread before I saw this thread: Custom Actions is Now in Beta! - #3 by grid7
This Loom reproduces what I’m seeing:
Loom | Free Screen & Video Recording Software | Loom

So @mkerp you were able to at least get to the point of receiving data in Zapier catch hook but you can only access the raw json (not the key/value GUI way)?