The browscap.ini file this plugin relies on is outdated as I write this (version 2.1) as it won't detect the latest version of Chrome in Linux Ubuntu 11.04.
After downloading the most recent version from http://browsers.garykeith.com/downloads.asp, it detected it just fine.
Since this plugin completely relies on the browscap.ini data to detect the browser, I recommend adding a WP_Cron task that compares the version currently being used with the latest version via their Version API, http://browsers.garykeith.com/faq.asp#FAQ_8, and then updates the local version if a newer version remotely exists.
The update can either be automatic or just prompt the administrator.
Here's how I've implemented the version check: http://pastebin.com/HudNEZTg.
It simply checks for a newer version, but I haven't added any sort of update function.
I hope that helps...