A few things.. Rated 4 out of 5 stars

This does work, I'm impressed. I will list a few things that are needed..

Support for opening CHM files from a web page. Support for viewing CHM files from the Archview extension.
Push buttons should (+) (-) display only if the section has 1 or more articles.
Index: Find as you type.
Search content (not to sure how easy this will be to implement)