Hi, I had this problem too, and have resolved it. In my stylesheet there was an element:
div#content p span {
background: none repeat scroll 0% 0% rgb(252, 252, 252);
}
Actually that's what it said when I inspected the element in Firefox. In my actual stylesheet it looked like this:
div#content p span {
background: #fcfcfc;
}
I removed it and now the button shows up. I think that stylesheet element was leftover from the original file, which I have edited a lot since installing.
It now works here: http://www.kirstenbasford.com