creating lines, brackets

For the angled line with the square "hooks" at each end, click the first note to select it, then Ctrl+click the last note to select it. Add a Line from the Lines palette. Then click the line itself to select it and, on the Properties tab, Style section, change its Start hook and End hook to the square corner. Finally, you can move the "handles" (the little square boxes) to adjust the line's position.