If you haven’t already started editing 2011, I would suggest using a child theme so that you don’t lose your changes if 2011 is updated. You can copy the header.php
file from 2011 to your child theme and make your changes there.
Remove the header image by going to Appearances -> Header and clicking the “Remove Header Image” button.
You can add the slideshow on line #111, right above the opening tag for the nav:
<nav id="access" role="navigation">
Make sure you use the template tag in this spot:
<?php if ( function_exists( 'meteor_slideshow' ) ) { meteor_slideshow(); } ?>