ADFS Certification & Proxy

Hello,

I am in need for some assistance with this ADFS issue:

We currently have and ADFS server 2008 R2 which is in a .local domain and is authenticating with the AD for a cloud proxy solution. I would like to install a proxy server which will allow external access to the ADFS, however I understand I must match the certificates on the ADFS with the proxy.

My questions are:

1. How can I replace the self-signed certificate currently installed on the (.local) ADFS server, with our wild-card public certificate? when i try to do so, it shows an error that the certificate does not match the server.
2. How do I sync the ADFS server with the ADFS proxy - certificates-wise?

Thanks in advance!