What exactly are you trying to setup? It goes through a router, so it should use the router's IP
address subnet and not one that a VM issues.
If it will help, drop me a short mail to dj0qn (at) darc,de and I will send you my networking checklist.
This list should be agnostic enough to work on a mac (you would run Setup Manager in the VM).
73,
Mitch DJ0QN / K7DX