Thumbnails won't load on two galleries

Hi, I’m using the latest version of the plugin.

Two of the galleries won’t show the thumbnails.

http://tinyurl.com/kgcubkv – thumbnails won’t show

http://tinyurl.com/kwncscd – thumbnails won’t show.

The other galleries show the thumbnails and work fine.

Thanks!

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