I'm hopeless. lol.
I followed your instructions, made the INI file using DOS like this said, change it from auto to the monitor I want to use. I even tried different numbers to make sure I'm not being dumb.
No matter what I do, MAME opens in full screen and it always opens on the same monitor.
Now look, I can live with it like this... but I just don't see why its being so difficult.
If you've lost your patience with me I understand. Sorry.
Thank you so much... I just wanted to play some classic games like the Ninja Turtles Arcade and other stuff on stream.
I love that there are people that know so much more about this than me and everything but I just wish it had an option in the settings
to choose a monitor.