Process in 'self-assign' ssl in Kloxo-MR:
1. Create .crt, .key and .csr file and then combine .key and .crt to .pem
2. Certain webserver using .key + pem (httpd and nginx), but other just using .pem (lighttpd and hiawatha)
3. If exists .ca file, webserver will using it also where .ca file related to ssl provider
In your case, try compare ca.pem and servercert.pem to .pem file self-assign.