size pictures

Hello, can you please check this page: http://www.avalon-buitenleven.nl/wp/gallery-millenium/

At the bottom of this page, there’s a nextgen slideshow.

In Gallery –> Options –> Thumbnails I set the size of the thumbnails on 340 x 255.

But the tumbnails stay smaller. How can I set the size of the pictures in this gallery?

Thanks for your answer!

Martine

http://wordpress.org/extend/plugins/nextgen-gallery/