For a general idea of how the plugin works, take a look at my blog. What
happens is that the latest entry in the category you choose for the comics
(I'll refer this to as 'comic entry') will be displayed at the top of the front
page under the title of "Latest Comic" and the other comic entries will be
hidden from showing up. They are visible in any other page, however.
As noted in the options, if you don't select any category, the plugin is
disabled.
The comic entries automatically get First/Previous/Next/Last navigation
links. This won't show up if you only have one comic entry since there's
nowhere else to go. If you're at the far end of the entries, obviously the
link to that end won't show up. That's why the latest comic entry will only
get First/Previous links.
Ideally, you should just have one <img> tag containing the comic in your
comic entry and have the 'raw' option enabled (default setting).
If there's any more questions, feel free to ask.