Totally understand - free is good!
If it helps at all, I think the issue I was seeing isn't the root, but part of the chain. Specifically the COMODO RSA Domain Validation Secure Server CA certificate. Sometimes this can happen if the full chain isn't installed, or, and perhaps more likely, it could just be that my browser isn't having it. Either way, I appreciate the HTTPS so I'm not going to complain.
Thanks!