Grace38, from what I can see the upgrade is significant. The control panel in the Admin section offers a lot more options. Also one of the bigger advantages is the ability of Lightbox to work on other pages aside from just the product detail page. For example it would work on pictures on the EZ pages.

Having said that, I am not having much success installing it on my site at http://www.syzygypens.com

I uninstalled 1.4 and installed 1.5. It shows up in my Admin panel, I can see and change all the options, however it is not working on the site. When I click on an image, the larger image is opened up in the same window and I have to click on the browser back button to get back to the product detail page.

I've been trying to figure out what I'm doing wrong for a couple of days now. I'd really like to get it sorted as I like the extra features of 1.5.