Can't sort or delete

Hello

I’m still trying to figure out why I can’t sort or delete photos with WP Simple Galleries – if I drag a photo and save post, it just won’t save the position.

I would look up for alternative gallery but your plugin is exactly what I need so I really hope I will get some response from this.
Thanks!

http://ww.wp.xz.cn/extend/plugins/wp-simple-galleries/