Hi Steve,
Ah, it wasn't clear from your original posting what you were getting, and since I couldn't see the content of your variable holding the actual address I couldn't comment on that either. Note that you shouldn't refer to the WebHelp documentation when working with EWriter, because the latter works differently in a number of ways, even though its contents are WebHelp.
it says "Normally, a link to a topic file will automatically display the entire help with the TOC
Thanks for noticing this. That text needs to be updated because this setting is no longer on by default. In WebHelp on the Internet the automatic redirect that reloads the full user interface when a topic is addressed on its own has to be off, because Google interprets the reload as "duplicate content" and an attempt to artificially increase click count, and then stops indexing the site.
You can turn this on again for regular skins in Configuration > Publishing Options > WebHelp > Navigation with the option "When a topic is loaded outside the navigation frame...". However I would
NOT use this for your EWriter calls. It is much better to do this directly with the index.html?topic.htm syntax.