Howdy, this seems a fantastic plugin, exactly what I was looking for (if a bit intimidating in the dropdown for non-technical users...who shouldn't really be in there anyway).
Upon install, if you choose to activate from that screen, you get a WP dead screen with "plugin does not have a valid header" message. If you activate it from the plugins main page after installation, all is well.
I believe it may have something to do with the whitespace between the comment blocks in the plugin's main file--I think there should not be a blank line between comment blocks. But that's just a guess for the moment.