What's wrong with my MX Records?

[Ironic Namesake]

I have one .co.uk on my Google Apps e-mail, and just wanted to add a secondary domain. I entered all the MX records as shown, but they fail to validate?

I've tried to send e-mails to the new domain, and it arrives in my Gmail inbox just fine

Here's the MX Records I'm using (from MX Toolbox)

Thanks in advance for any advice !