I have several projects which generate chm's. I've merged them into a single project and can then generate a chm which contains everything...
Hopefully you realize that you don't end up with a single .CHM that contains everything from the merge. What you get is a .CHM that presents somewhat of an illusion. When it is launched, it lists the TOC and Index entries of all the other individual CHM files you told to merge with it.
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