SPRY WITH THICKBOX OR GREYBOX

I know this is an old post now, but if it helps anyone. I had the same problem as the OP with GreyBox but reading the FAQs on the GreyBox site I found the answer.

To use GreyBox with spry you need to use the onclick= command as detailed in the advanced section in the GreyBox instructions, and not the rel= command as detailed in the basic section.

Example: To show an image inside a spry region, where the image name and image title is retrieved from a HTML dataset, this is the code you would use.

<a href="images/{ds1::img_full}" onclick="return GB_showImage('{ds1::imgTitle}', this.href)">Show Image</a>

The image name is the name the image is saved as and the image title is the title you want displayed in the GreyBox title bar.

Using the onclick= command the image will open in a GreyBox window. Using the rel= command the image will open in a normal blank HTML window.

Hope this helps.