An error occurred while working with "Labels"

I CAN'T get this thing fixed.

Having disposed of my planning workshop with the city's Disaster Management sector, I rushed back to the office to take advantage of its DSL connection and continue my adventures with the new Blogger Beta with HTML editing.

I have just tried adding the "Labels" widget -- Blogger's answer to Wordpress' "Categories" and Del.icio.us' "Tags." It works just fine because the process is pretty straightforward; as one writes a entry, there is already a "Label for this post:" window where categories can be created and organized.

I also added the Blogger logo as another page element.

As can be seen here, it already forms part of my sidebar.

My problem started when I tried reorganizing the sequence of the widgets. What I wanted is the following sequence from top to bottom: About Me, Categories (previously Labels), Archives (previously Blog Archives), Links and finally the Blogger logo.

For at least 10 times I tried saving these changes to the Template. But to no avail: I always get the message "An error occurred. Please try again."

Is this a bug that the Blogger team needs to fix? Or can it be that the new software frowns on the use of "Categories" in place of "Labels"?