switching nav menu with categories ????

would it be a lot of hassle to have the main nav menu below the header instead
of above it and simply remove the categories ????

not really, depending on how adventurous you’re feeling.

first backup the theme’s header.php (copy it to a new header-old.php file) and replace the second <div class="span-24">MORE-CODE-HERE</div> block of code with the first <div class="span-24">MORE-CODE-HERE</div> block of code

I’d also then change line 36 of the theme’s style.css file to something like (add margin-top):

#header {
    height:90px;
    margin-top: 10px;
}