I have the very same question...

Okay - I've had a look in the books section, and found that you had two spines set up for this tale.
I've deleted one of those.
Then I hunted back for your two previous chapters, and set them all into the spine for you.
There are a few issues with the book spines, but it's being looked into.
When you're ready with chapter four, go to your spine and, you should be able to add a child page (to the right, just above comments)
Set the title, and drop the book pick-list to Institutionalized, and select that.
Skip down to the bottom, below the BODY section, and select BOOK OUTLINE
All being well, the book box should have your book selected already - if not, select Institutionalized.
The PARENT ITEM drop-box should be set to the top level of your book - in your case, institutionalized.
Finally, the weight should be set in a decreasing order - chapter 1 is -15, chapter 2 is -14, and so on. So Chapter four should be set at -12.
Save it, and hey presto - all done.
Any problems, send me a PM. :)

It's like learning science out there :S

I had the same problem, so I just asked Verm to do it. He's the daddy of all things technological and techi-fied (& a thoroughly good egg, too). Thank you Wonderthrax.

The book stab a few questions, but it looked. When you are ready to your spine, you should be able to add a HP 02 sub-page.