Thanks for your help!
It turns out that I was getting a insufficient privileges error because the page did not exist.
This is technically beyond me, but for whatever reason why I tried to install the plugin from the wp-admin (plugins > add new), it downloaded version 0.2 (or an entirely different plugin?!) which explains all my problems.
Fixed by installing the correct way per your install instructions (sftp into the wp-content/plugins/). Thanks again for your patience and willingness to answer questions!
“You do not have sufficient permissions to access this page.”
I assume this is a 3.6 problem, since everyone running 3.5 doesn’t seem to have a problem.
Do you have any other ideas?
Thanks for looking into it and I appreciate the tip. I’ve asked everyone in my small office to look into it, but they can’t see anything either (they are all on PCs).