Captcha on Custom Login Form

HI there.

I cannot get Google captcha to work on “custom login forms” .

I’ve enabled the captcha functionality and included my Google info.
Use Google reCAPTCHA as default: Checked. Site key and secret key have been enabled.

For the “custom form” I’m using very basic wp_login_form() to test and although the captcha is displaying it is only returning with the basic maths challenge–not Google version.

Any ideas or a blog post on the full implementation on how to get this to work with the wp_login_form php?

Thanks!

The page I need help with: [log in to see the link]