Page numbers in the Advanced Editor are assigned by the system as you create them. You can't change them or re-order them unfortunately.
You can however, organize your stories to some degree by using Chapters, but if you do that, you'll want to become familiar with the $DEST := @P100 Script so that you can make your links jump from page to page across Chapters, where right now, the Graphic Interface only allows you to jump from page to page in the same Chapter and only the Start Page of other Chapters.
If you haven't already, I suggest creating a Test Storygame and trying all sorts of stuff out in it to see what you might want to bring into your actual story.
