Hello Tom
I do have a connection. I see it in Indi Control panel.
I am using the Arduino with a relay board and sensors connected testing on the bench. 
One relay for open another for close and 2 sensors for open and close.
I am using the rolloffino.standard file for the Arduino. That seems the closes match for what I have for testing.
I did manage to see some action on the Arduino today. I set the sensors as expected and Indi sees it as well.
If I hit the open or closed buttons in Indi I see the corresponding relay come on but then the Indi driver Rolloffino crashes and a few seconds later Kstars crashes.
I have attached a zipped folder with log files.

@ Jasem
You indicated that I should be able to use the same process from the HOWTO: Building latest libindi and Ekos on a macOS.
I tried that and get a message: "sudo: apt-get: command not found".
Do you perhaps know what I may be  doing wrong.

I have tried