How do have three little photos and one large one.

have seen in the templates a set up of photos. eg 3 little photos one large one, when you roll over the little ones they become big in the same place as the big one. I do not yet understand the layer bit, so if I could get a description of how to do this it would help

I moved your post into the Xara Web Graphics Chat. You posted in the Graphics Chat forum for non graphic products.

This can be done with layers. You create a new layer in the Page and Layer Gallery, add your large image to the new layer.

Then on the Mouse Off or Layer 1 layer (depends on the product you are using), you add a small thumbnail image and link it to the layer with your larger photo.