I recently deployed BlogEngine.Net 1.4.5 and found a few typos in the Widget Titles such as RecentPosts and Tag cloud.  After searching all over and trying all sorts method to change this, I came across a post at the CodePlex forums that solves this problem.

How do you change the BlogRoll title?

Worked like a charm. Just have to remember that any future updates may wipe out this change.