Never mind - easier just to remove them and add again specifically for the gallery. Thanks.

Hi, thanks - I've tried all of that, but if I don't 'Insert into page' then there are no photos in the gallery, and if I do insert into page, then the gallery is empty and all the images are just inserted into the page one after another. Any ideas? Thanks.

How do you insert media that is already in your Media Library, using the new media dialog in Wordpress 3.5?
Thanks,
Anthony