I would like to raise the melody by one octave for the second chorus of my song, in another word for a given set of bars. When I use Crl-Alt-2 it raise the melody for the whole song. How can I do that?

Thanks in advance for your help.

Try ALT-L-E-T. It is the transpose for the melody. The options include 1 octave up or down, but just chose Melody only. This allows you to pick the bars you want to change, and well as the number of semitones up or down