change instrument name

Hello!

I can see a lot of improvements in ver 1.0.

Question: how do I change the name of the instrument listed at the beginning of the piece. For example, I would like to change 'Tenor' to 'Part 1'. Before, I could just double-click on the word. Now that doesn't seem to work. I also want to get rid of the T. abbreviation on subsequent lines.

Thanks in advance,
Ryan