I’m not network savvy (someone else set up the network for me some time ago) and i’m aware that being connected to the internet all the time is not ideal, but it works for now.
In the Cubase iC pro Official Video Tutorial thread on this forum Mr.roos has put a lot of info that may help you.
It seems that in my case (even as a complete idiot) I was lucky and it worked, so I don’t want to try to change things at the moment.
Note. The app does not list anything in the connection box on the nexus so I have to enter the IP address every time.