I updated my CS407 to the latest beta firmware today and when I'm on the login page, I see the new items that say "Management", "File System", etc... I was using Firefox v2.006 and those items just appeared as links/words. There was no indication of which one I had clicked on. I then tried IE7 and could see how they are actually highlighted when one is selected before logging in.
Here's what I found. When I type the IP address of the CS407 into my Firefox browser (like 192.168.1.150:5000), I get the error of the HTML not looking correct. If I remote in via a DNS (like the EZ-Internet feature), it works fine via Firefox. IE7 seems to work fine all the time. So, I'm not sure if this is something with my browser/settings/plug-in or something that can be duplicated by other users to indicated it's actually a possible bug.