Geraldine,
I've done this, but it's been a long time. You know where to do this, right? Options>Index>Locators, then in the Page Ranges section, click on Create a new conflation set. (I was hoping someone else would chime in brilliantly with the best ideas for doing it right, but not so far...)
The best way to start is to use CMS 16th and 17th and then Create a new conflation set. That way it will start with CMS.
It looks to me like you'll need
1-20, don't elide, repeat 100s, 3 (how long is your book? will it go into 300 pages?? If it only goes to 250 pages, then 2 is fine here)
21-99, changed part, repeat 100s, 2 or 3 will work here
See if that's enough and delete everything else.. If it isn't, then refer to the CMS 16th and 17th and put stuff back in to fill it out. The 16th/17th one is set up for a book of 2000 pages and if yours is shorter than that, you won't need as long a table.
Let us know what worked --
Deborah
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