Hi,
I specialize in fixing issues, and making sites (both user side, and programming) tidier and better. I can fix all your issues, and improve your site all around.
I took a look at your site, and to fix the gallery, I would swap out the current gallery Javascript with a proven, open-source solution like Lightbox.
I have my own website where I make changes, so I can do the work and show you the results without disturbing your live site, then upload the fixed files late at night or early in the morning to minimize disruption.
I would love the opportunity to discuss this project with you.