Hello, thanks for the happy words and questions.
Normally, "Random Compose" will set scale to "Magical Scale1". This is is to make the melody not dissonant with the chords generated random chord.
But if you click the button with pressing SHIFT key, it will generate a melody based on the scale you have selected, without changing the scale. (And it will also not change the tempo or delete other parts that are not selected.)
And If you right-click on "Random Compose", then melody will not generate.
Also "Random Melody" button will only generate a melody based on the scale for the selected part.
Can you do what you want with these?