when more monitors are in use on the server, NoMachine captures the whole virtual screen extending on all monitors. As the client is set to scale the captured screen to fit in its window, you could find that the resulting image is too squeezed if the server screen is much larger than the client window.
In case like this it is better if you set the client not to fit in the window: run the NoMachine session, press Ctrl+Alt+0, click on “Display” and turn off the option “Fit to window”.
About the keyboard, please send log files to us in order to check for possible problems. By the way, what you described looks the expected behavior. The layout that matters is the one set on the server. You need to change the server setting in order to match the client keyboard.
You can find instructions to gather server side logs here: https://www.nomachine.com/AR07K00677