Order complete problems – Worldpay breaks site and doesn't redirect to right place

I'm having a problem with Worldpay. For the most part it works fine, with a few big errors:

1. The order confirmation page is buggered (see attachment). It seems to be serving the page from Worldpay's servers which is odd. I'm also using Typekit for fonts, and these have disappeared as well. Is there a way to theme this page - either keep the Worldpay payment pages theme or turn off bits on my site so it doesn't look so bad?
2. The automatic redirect goest to /cart rather than a confirmation page. As the product is still in the cart and there's no confirmation message (other than the broken Worldpay one) it could be confusing to customers as to whether their order has been placed. They are also not automatically logged in, even though I've set that option
3. The admin is not sent an email to say an order has been placed. The customer gets an invoice though, and Worldpay fires of emails all over the place. I've checked the rule and that seems to be ok, so I'm not sure what the problem is.

Any ideas to these problems?

You can see the site here: www.chadwickoven.com

Cheers,

Matt