I have never used the expansion pack, so I can't really give any advice on that.

However, in regards to the "Listen" that is on top of the screen (in between the ON and OFF buttons), that is actually an image file, not text. You can rename the "Listen" on the tree on the left side of the simulator page, though.

To change the "Listen" on the top, you would have to manually take that image and edit it using some kind of photo editing program or something (like PAINT or Photoshop, etc.), then re-insert the modified image onto that spot. The background is black, so it is fairly easy to paint over the letters and add your own text or whatever graphics you want.