I'm writing this one just as a help for someone that might struggle to get the "Ctrl-J" (Show Madvr OSD) to work. I was trying it for quite a while and couldn't get it to work, not matter what (I read some posts here about having to move the mouse, click on the screen, etc, but still wouldn't work).
What fixed it for me was that in the options menu, I had under "Remote", not just my MCE remote selected, but also mouse / keyboard. After leaving only the MCE remote selected, restarting the player, I can still use the mouse / keyboard inside the player, but now if I press Ctrl-J, I get the Madvr OSD to show...
Cheers