1:Bookmarks. When you create a bookmark, a small file is created that points to the page you are bookmarking. You can then search and load this bookmark like any other file but all it does is load the large PDF and turn to the page you have bookmarked.
2: Export pages window. You can export a page or a number of pages as a separate file. This will basically create a new pdf from the original file.
3: Indexes: you need to create these
(see the help), but this a file that has a listing of all of the songs in the real book. You can search and load these indexes and choose from any of the songs listed and the PDF file will be loaded and turned to the page.