Enabling In-browser elevated trust

I'm trying to get in-browser elevated trust to work and having an issue. I've:

1. Purchased a certificate
2. Signed the xap with that certificate
3. Added AllowElevatedTrustAppsInBrowser=1 in the registry

Yet the app still doesn't think it is running in elevated trust. Any ideas on what I might be missing?

Running off localhost, of course, works because it doesn't require any of the above.

Screenshots included below as proof.

So you have your certificate from a trusted publisher. You have signed the XAP. You have installed the certificate on the client computers.

Have you configured the registry on the client as described in this post?

You can also configure the registry settings using Group Policy