StellarMate has the Serial Port Assistant, but KStars/Ekos on the Mac does not. When I try to connect my CEM70, Ekos cycles through several driver/port choices, including one that looks like an old Keyspan USB-to-serial adapter I used with my CEM25P, one with Bluetooth, and one that looked like it might be USB but didn't connect.
Normally I just use my Pi but occasionally need to connect directly with the Mac. The cameras and filter wheel connect just fine, with no setup on my part. Any suggestions on where to start?