Select menu File | Open MIDI File(s) to open a file for conversion of Mega Voices (if present) in the file.
Select channels to clean manually or use 'Select All' or 'Select None' buttons.
Press button 'Clean'
When processed the Save MIDI file dialog will open automatically.
By default the processed file(s) will be named "_" + original name; e.g. "_AmazingGraze.mid".
Accept the default name or rename the MIDI file(s) to any valid name of your choice.
Save the MIDI file(s) in a folder of your choice.
Select menu File | Exit to end the program.