I was looking at another thread and thought I should clarify something here.
Unless the latest version of nexgen has been ‘fixed’ it’s been the case that by default NextGen uses the Descirption (i.e the LARGE input box) as the Caption.
Many people, myself included, regard that as wrong because if for example you have a long description or you put html in it then it will cause significant layout problems.
Ideally NextGen should use the Alt field (i.e the one line input box)as the caption and that can be achieved by amending the code as in the posts referenced above or as found elsewhere in the forum.
So, in short, for someone with a stock NextGen install the Caption is derived from the Description field. For a customised Nextgen like mine the Caption is drived from the Alt field. In both cases you need to use the template=caption shortcode.
many thanks for getting back to me, and sincere apologies for not replying sooner.
I have quite a lot of questions on the nextgen gallery, would you be able to try and answer for me?