This is a bug, it’s because you’re using PHP 5.3.0 and the code on the lines it references has been deprecated in PHP 5.3.0 to be removed in PHP 6.0. What I’d do (and did do) is downgrade to PHP 5.2.11 until the code is fixed to be 5.3.0 compatible; I got the same errors when I had it on PHP 5.3.0, downgrading sorts it as it’s OK code for PHP 5.2.11. It’s very simple to downgrade on WAMP, I’m not sure how you’d go about it on XAMPP though. Turning off the errors will still work, yeah, because the code will still physically work with PHP 5.3.0, but it’s just letting you know it’s due to be removed.
That’s for the four errors about deprecation, for the Cannot modify header information error, may be related to the PHP 5.3.0 errors too as the error in bb-settings.php is on the same line as the deprecated warning.
