Anti-Slog can not install - No Header

Dear All,

Just tried to install the anti-splog but does not work. The message was "no header". What is going on? and how to install it?

It happened also in two or three others plugin from here, but forget to note it and inform you. will do it later.

I'm using WP 3.0, Multi-Site, BuddyPress the latest update, BP Daily Theme