Foren / Cotonti / Extensions / Support / Page Archive outputs everything?

I installed the Page Archive plugin, which is great btw but I am having one problem with it.
http://www.cotonti.com/extensions/navigation-structure/page_archive

I have set in the admin panel to ignore system pages, but it still outputs those.
Additionally, no matter which section I specifify in the {PHP|pagearchive('xxxx')}, it always outputs all sections.
I have 3 sections; news, files and documentation.
When in the files list I set {PHP|pagearchive('files')} it will list only the months in which files have been added to that list section. But if you click the month it outputs everything (all other section, news and documents and system)

Is this a bug with this plugin? I noticed it is already a few months old and maybe something changed?

I am using the latest version of Sienna.