To install desktop shortcuts, edit the two .desktop files so that the
path to the icon and executables are correct.
Then copy the two files to your desktop.
The files in the program folder will be overwritten if you update MMEdit 
into the same folders but your desktop versions will be safe.

If MMEdit fails to run, you probable need to install some libraries.
From a command prompt run
sudo apt-get install qt5-default libqt5webkit5
