SINGLE ZOOM IMAGE

Hallo. I am busy designing a wedding gown website. There are over a 100 images on a page of wedding gowns. The person can click on the image and will automatically enlarge the image. There is a problem however. I have used the landscape gallery images, I deleted the rest of the pages and used the first one (image gallery) and copied it to the web page. The problem is on preview on xara it works great, but when it is loaded the images next to each other do not work. The first one on the right for instance will "blow up" when I click on it, but the image just next to it wont work, even after I've tried numerous times to redo the images. I think they overlap each other..What I like is that you can resize that it fits, because some of these dress images are quite big. Is there a another option to try? Maybe a quicker solution.
Thanks