Looks good code-wise. Mind showing a screenshot?
Updated the template file for the Extension Configuration page
Review Request #2883 — Created Feb. 13, 2012 and submitted
The new admin stylesheet was not being pulled into this page. I also removed the breadcrumbs and added a header to the form to bring it in line with other fieldsets.
Testing done locally on Windows 7, Chrome 18.0.1025.11 beta-m and IE8, fits in with non-dashboard pages.