Connecting Net3 RFR to ETC nomad on OSX



how do I connect an RFR base to ETC Nomad on MacOS?

_via USB to the MacBook: does not work

_via USB to Cobalt Programming wing: does not work

_via Ethernet: does not work


What's also puzzling me:

When the CongoJr is running as Server, I can see all my Net3 devices including the RFR base.

When Nomad is running as Server, I cannot see any Net3 devices (although DMX is output correctly through 4-Port-Node)

(Switching off the Firewall on the MacBook doesn't help here.)