We're running a Multi-Site environment powered by WordPress 3.3, the registration process is redirected towards wp-signup.php, even when accessing wp-login.php?action=register, so naturally the latest version of the addon (1.2.11) does not redirect properly. function custom_registration_page() contains a $script_name != 'wp-login.php' || $action != 'register') that will evaluate to true and return thus no redirection for us. Had to add an additional $script_name != 'p-signup.php' condition to let the hook fall through.
And we then did realize that wp-login.php @line 481 http://core.trac.wordpress.org/browser/tags/3.3.1/wp-login.php#L481 explicitly says: // Multisite uses wp-signup.php, so either we're missing something here (although a search for 'signup.php' does not yield results inside the Gravity Forms addon code) or this feature of the addon does not function properly with Multisite.
