Hi all, does anyone know if it's possible to pre-load a default image in the Gallery Block based on a Page Thumbnail Attribute?

I'm working on a Page Type which users add a Page Thumbnail to when a new page is created. On the page I have a Gallery block which I would like to use the Page Thumbnail as the first image.

Any ideas?

Alternatively is it possible to create a Page Thumbnail attribute from the first image in the Gallery Block?

Thanks,
Mike