Having problem with updating home page slider

We have a slideshow on our home page with four pictures. We are trying to switch out one of the pictures on the slideshow. The problem is, I don’t know how to get to the slideshow to make the changes. Someone kindly referred me to the Travelify forum as the slideshow may be part of the theme setup. I would appreciate any help I can get on this. Thank you.

The page I need help with: [log in to see the link]