An alternative way to source a file via MEL is type
source "fileName"; in the script editor . . .
You do not have to add the .mel . . . .
Then highlight ( select ) it, and hit the Enter key on the number pad.
If you hit the other enter key, after you select it, it will only dissappear.
"The Sage as an Astronomer: If you still see the stars as something above you, you lack the eye of knowledge." Friedrich Nietzsche