Can't Edit Staff Text Line

When I add a staff text line, I am unable to edit the word, "Staff". I want to change "Staff" to "Sostenuto" in italics. Pressing [F2] or double-clicking on the text doesn't do anything. What am I missing?

Also, I don't see any way to change the direction of the end hook. From the palette, the default is a down hook. I tried changing its height to a negative number, and that seemed to do the trick. Is this the correct way change from down hook to up hook?

Thanks.

— Herb