The XPJ only exists in the source of each project of the
merge and in each source, you will only see the index and TOC for
that project. When you generate and / or publish you get the
output. The is opened by running the start page for the parent.
That is defined in the first page of the wizard and there will not
be any XPJ file there. Indeed, if there was you would have a major
problem.
Take a look at the topic on my site about merged webhelp and
all will be explained. There will be references to the MPJ file,
rather than XPJ but it is otherwise all still valid.
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