This will help you get a signed certificate for your dn42 domain.
Download the client shell script from the link below
Ensure your MNT object in the registry has an SSH-based authentication method and that you have the key available
Run ./client.sh get_certificate <domain.dn42> <path to SSH key> <maintainer name with '-MNT' suffix> (replace the parameters in brackets with the correct values) to generate a certificate and have it signed
Configure the signed.crt and server.key files resulting from the previous command in your webserver.