Thank you everyone.
I have managed to license my Mediacenter. For further information I will outline the steps that I took.
MediaCenter version 24
Linux: Opensuse Leap 42.3
My executable is located in /usr/bin/mediacenter24 (I had installed using sudo zypper in Mediacenter.......rpm)
I copied my .mjr to /usr/bin using: sudo cp -f "Media Center24 Master-123456.mjr" /usr/bin
Then cd /usr/bin
Finally ./mediacenter24 ./"Media Center24 Master 123456.mjr"
Up popped the successful registration box. I had tried doing the above as root and su. In both cases I got the successful registration flag but when I closed and reopened MediaCenter the license information said that the product was unregistered. My successful registration was using the account that I had used when installed the .rpm package originally.
Thank you again everyone. i will try not to be a pain in the future!