Hi Grant,
Thanks for the suggestion. I'm already using the MorfeoShow image gallery and have found that it's a little harder than you might think to get a decent output.
Part of the config requires you to go back to the underlying code used to develop the Joomla module, and support for this through the MorfeoShow forums is pretty patchy (I've not had any replies to my forum posts, but that could me just me

)
To achieve my goal of generating a lightbox from a thumbnail image loaded in a module position, I used the simple JCE Utilities plugin. Simple to install/setup and works as required.
As I've seen with MorfeoShow it's much more a "full-blown" Gallery. That said I'm removing it from one of my sites and going back to RSGallery.
Hope that's of use.
Martin