I have created a project that includes a Captivate tutorial
that will only be available in the webhelp output, not in the CHM
output. I have excluded the topic that includes the tutorial from
the CHM output using conditional variables, but strangely enough,
the size of the CHM file is still increased by about 500 Kb.
The only "solution" I have found is to rename the .swf files
in the project folder before compiling the CHM output so that they
are not "taken into account" in the CHM compilation, and give them
back their original name when compiling the webhelp.
Likely the Captivate is stuck in the project. I don't believe
there is a way to exclude it as you would like. Well, other than
what you are already doing.
You (and others) should really report this behavior as a
bug/wish so that the developers can be aware we need an ability to
apply Conditional Build Tags to content in Baggage and Multimedia