cannot access this plugin from settings in admin

hey all,

I have this plugin:
http://www.softsift.com/wp-content/uploads/thumbnailsummary1.3.zip

and after it is activated and I try to go to the options for it under the settings tab in the admin, I get a page that says I do not have permissions to access this page.

I am the admin so I dont know why it is telling me this. Plus all my other plugins work fine from the settings tab and I have no problem logging into wordpress.

Can anyone help me pick apart this plugin or maybe try to install it on your blog and see if you get the same error when trying to access the options for this plugin from within the admin?

thanks in advance.
tom

i am using wordpress 2.8.2