Merged project

[Judy Bragg]

I'm using Tech. Comm. Suite ( FM8 ver. 8.0p277 & RH7 ver. 7.02.001) to generate multiple user manuals (a full manual and 3 quickstarts) as well as CHM Help files.  (Windows XP SP3 if it matters.)
The manual has 10 chapters, each in its own FM book, complete with TOC and IX.  All chapters are added to RH by reference and each is compiled to a CHM.  So far so good!
The problem comes when I try to merge them.  The TOC is OK, but the Index is wrong.  
Here's what I did:
I used the first chapter as the master and merged the other 9 onto the end of it.  (In the ch. 1 TOC, I clicked the New Merged Project icon and added the ch. 2 chm.  Repeat the process for chapters 3-10.)  In the HTML Single Source Layout, I used the merged TOC...what should I do with the IX field?  
I tried adding IX placeholders to the end of the ch 1 IX, but the result was 10 catenated IX files.   They don't merge.
Theoretically, I suppose I could generate the full manual in 1 FM book and reference it in RH, but it takes forever to update that many files and I've noticed the system tends to fail one way or another when I attempt to do too much.  Also, I have to produce a modular system patterned after the previous one.  Changing the help calls in the numerous program modules of our software would be our last resort at this point. This way I can do 1 chapter at a time and the TOC's  are easily updated from the FM file.  Now if I can just get the index to merge...
Can anyone please steer me in the right direction?  I would be forever grateful!
Judy Bragg
Technical Writer
Hypack, Inc.