[Plugin: AskApache Password Protect] Fatal error and php code

I installed the latest version of this 4.2.4 and when I activate it says ‘Fatal Error’. Then you click on ‘Activate’ and it shows php code and Configure it gives a message that I see other posts have posted regarding it being powerful and can take down your server. Help please.

http://wordpress.org/extend/plugins/askapache-password-protect/