Answered: can anyone solve these webmaster plugin errors displaying on admin page header?

OK I've tested the plugin and managed to fix the notices with the following changes:

qa-webmaster-layer.php line 5, change to

function __construct($template, $content, $rooturl, $request)

qa-webmaster-layer.php lines 462, 464, 466 change each of them to

$val = (int) $val * 1024;

library/security.php, line 16, change to:

$security'magic_quotes_gpc']'value'] = 0;

Hopefully that should be everything!