[Plugin: Category Grid View Gallery] settings

I’ve been looking for this for so long…and now that I thought I had it made 🙂 it says when I go to the settings part

“You are not authorised to perform this operation.

I sure hope you have an answer for me as this is what I specifically need.
I have the latest plugin too.

http://wordpress.org/extend/plugins/category-grid-view-gallery/