First of all thanks for this great plugin! We have an conflict with jQuery and the jQuery UI library you use in your plugin. Another user also mentioned it in the following topic:
http://wordpress.org/support/topic/error-has-no-method-curcss?replies=3#post-3964190
Could you please update the jQuery UI library to the latest version?
You can use the following jQuery UI download:
http://jqueryui.com/download/#!version=1.10.3&themeParams=none&components=1111000000100010000000000000000000
Or directly via the following Gist:
https://gist.github.com/remcotolsma/5531421
And adjust line 152 in 'gfcptaddonbase.php' to:
http://plugins.trac.wordpress.org/browser/gravity-forms-custom-post-types/tags/3.0.1/gfcptaddonbase.php#L152
wp_register_script(
$handle = 'gfcpt_jquery_ui',
$src = plugins_url( 'js/jquery-ui-1.10.3.custom.min.js' , __FILE__ ),
$deps = array('jquery'),
$version = '1.10.3' );
I hope you can launch a fix soon.
http://wordpress.org/extend/plugins/gravity-forms-custom-post-types/