WPMU Dashboard Not Showing Up After Installation

WPMU Dashboard doesn't show up in my left column dashboard. I tried downloading it again and uploading the zip file as a plug-in, but I get an error message that the folder already exists. I just tried to add the popup pro plug-in to the site, but got an "You do not have sufficient permissions to access this page."

I'm using a theme called WP-Drudge. I use it a lot. I'm hoping that's not the issue. Any help would be appreciated.

I'm attaching screenshot of my dashboard options, if that helps.