As mentioned earlier in this thread, pop up layers are just as functional as pages, so you can have a link in a pop up to open another pop up. So you could let the reader click on a link for next page or more or whatever word you choose to open the next pop up with the continuing text. I don't use the close automatically option when doing this, but rather a dedicated close button that will close all open pop ups at once so when done reading the user clicks that and is right back where they left off. It is easy to copy/paste in place the pop up so you only see one at a time. Just another option that is available to you.