Using my own Security Certificatein KepServerEx

Hi, I was wondering if it is possible to use your own security certificates with KepServerEx for OPC UA communication. I've seen that there is an option to import certificates in the Instance Certificates section of the OPC UA Configuration Manager. Is there any information on the requirements for using your own certificates?

I also saw that there was a Certificate Store tab in the settings for KepServerEx. Is this for use specifically for ThingWorx?