I've used lots of xml in RoboHelp and think you have two
options here:
1. Static Output
RoboHelp 5 allows you to import xml and name an xslt
stylesheet for the transform. (there are also some default
stylesheets). If done correctly, this import produces a static html
page that can then be added and displayed by RH in the usual way.
2. Dynamic Output
If you need dynamic display of xml data, you're still going
to need a stylesheet, but will also need to create an html page
with javascript calls that transform and display the transformed
output. (with AJAX, for example). This puts you in the arena of
browser detection and using different syntax for different
browsers. (there is an additional annoyance of displaying local and
server-based output--at least in IE. Firefox doesn't need different
syntax). I use this latter approach and construct pages,
javascript, etc in an external html editor (Dreamweaver). RH thinks
my xml display page is just another html file. It's none the wiser,
and, as they say, stuff works. ((javascript, xml, xsl files must be
added as baggage files for this to work) You can also look at the
Sarissa Library on Sourceforge as a browser agnostic possibility.
Hope this clarifies your question,
Andrea