ArtNet Network changes between 3.7.1 and 3.12.0

Hi,
I was in "The Anthem" venue in Washington DC, and was unable to control their rig via ArtNet despite several attempts, and reboots.
The house console is a fullsize Hog4, but they have it running on 3.7.1.
I had 2 fullsize Hog4s with me, and tried copying their network settings... and even tried loading their showfile into both my desks... and still couldn't control it.
The strange thing was being unable to set a Gateway.... their console had 0.0.0.0 as the gateway... and no matter what I entered into mine, it changed to 0.0.0.0 when I applied.

I have a copy of their showfile that I can send, as well as mine.

I guess the reason I am posting this, is that if they update their software, then their showfile willnot control their rig (As loading it into my desks proved)... so I am trying to pre-empt a support call from them.

Any thoughts?