You should be able to do this now. If you run Media Server, MC is always available. And you can start a video full screen by changing the options in Tools/Options/General/Behavior.
I think I can explain what is happening.
First thing. If only and only media server is running I can hear sound but no picture. I have to have media center open.
For the full screen to work I must at least once manually make it full screen. If I remotely stop and start video it now starts full screen but if I make media center windowed during playback and stop start video if does not go to full screen, ever.
So resuming. Only media server running I get no picture. Media center running I get picture but full screen only If I made it full screen previously.
Still can get refresh rate to change and have to ignore mime check because video/matroska is missing.
Thank you