Just wanted to add that through trial and error and the help of this thread I was able to connect ARC to my EZ-B v3! What's more, I did it on my Macbook Pro, via Parallels, to Windows 10. I was able to update the firmware. I was able to open ARC and connect to the EZ-B v3.

What to do now I have no idea. ARC is not exactly intuitive and I think I want to let the frustration of getting this far settle before I do a bunch of reading.