Mininserver install doesn't poke a hole in the Windows 2016 firewall to let through traffic to the Lumin app on the ipad. For linux, UDP port 1900 needs to be open, made rules for both directions, didn't work. Switched off the firewall and the server could be seen by the Lumin app. Mamma mia, what a process. I could find the ports to open in Roon took a little time, but for Minimserver, it's a STRUGGLE.