Q:  The program does not allow to put in any notes on the treble clef below 
    middle "C" without moving to the bass clef.  


A:  If you are using a grand staff for a track, the split point is middle C.
    You can change the split point for a grand staff (Display>Track) but 
    here's another easier way: 

    If you want to put notes on the treble cleff below middle C, the easiest
    thing to do is to have two separate tracks: one treble and one bass. 
    You can set this up in the Track Sheet (Window>Track Sheet). Set one 
    track to treble clef and one track to bass clef. This way you can notate
    any note on the treble cleff (below middle C etc) without it putting it
    on the bass clef because you're working with two separate tracks. 

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