At the moment my images are just opening in a new window, see link:
link here

I have tried everything! Help would be much appreciated.

Thanks =)

<a href="/_private/images/DT.jpg"><img src="/_private/images/image1.png" rel="lightbox[example]" /></a>

The rel attribute does not belong on the IMG tag, but should be on the A:

<a rel="lightbox[example]" href="/_private/images/DT.jpg"><img src="/_private/images/image1.png" /></a>

If that doesn't work, try removing the [example].

amazing!! problem solved, you don't know how long i've been trying to figure this out! thanks a million.