Hello Dinga -
I don't use Win10 and I don't intend to. At the moment I have two Win7 machines on my network and two Win98SE (Second Edition) MP3 jukeboxes.
SuperBeast has my main FSX+Acc install in C:\FS10 and my old FS9.1 in G:\Classic FS. This arrangement fixed the clashes I was seeing when both were on the same physical drive, even though I was using different language.dll files. (which write changes to the cfg files in Users\App Data\umpty tumpty tum)
MiniBeast has a very basic install of FSX+Acc, mainly for rapid recovery when I accidentally delete all the default texture files, for example.
All the machines on my network talk to each other via an 8-port D-Link switch, and can reach the internet through my Dovado router, to my 4G wireless modem.
I can start an MP session on Superbeast, and join it from MiniBeast, where I have an aircraft carrier controlled by a stand-alone autopilot software. I can then fly in Superbeast and practice carrier landings. This works through the switch.
I can also join an MP hosted by Ian, logging in from both of my machines, when both Ian and myself can land on my autopiloted carrier, but my provider's security settings don't let me host a session which Ian ( or anyone else) can join.
Hope this helps