Multiple SRB2 servers

I have asked this numerous times, on various places, various people, but apparently cares enough (Yay, the SRB2 community is so helpful.) to help me out.

My VPS has two IP addresses.
I want to host multiple SRB2 servers.

USING DIFFERENT -clientport & -udpport TO RUN IT ON THE SAME IP:
Works, except it won't be seen on the Master Server. Yes, that is important. I demand an explanation as to why it doesn't show up on the Master Server and if there is any way to fix that.
If not, how on the face of planet Earth do I bind the thing to my VPS' other IP?

Thank you.

It should show on the MS regardless of port.

As for binding to a different IP, it's -bindaddr I think but I could never get it to work.