Test one bedroom computer, NoMachined into bedroom computer (gigabit ethernet on one wifi ac 5.2GHZ on the other) almost flawless performance(test passed, getting excited), test 2 connect laptop to same bedroom pc that the livingroom pc was NoMachined too(multiple issues) first off doing this killed the connection to the living room pc (it looks to be programmed to do this..
The free version of NoMachine allows one connection at a time. So when you connect a second time from another client to the same server, a dialog should pop up notifying you of this. If you want to be connected multiple times to the same server computer, you should try the evaluation of Enterprise Desktop. This will allow unlimited connections to the same server.