CloudFlare still isn't supported on his version; if he were to configure CloudFlare using a version that doesn't have the correct configuration to read the pass-through IP address from CloudFlare will result in every user who makes any post or logs in to his forums to have the same IP address (which will be the CloudFlare proxy)... Something that I would highly advise against.
If wanting to filter trolls by utilizing the built in Stop Forum Spam feature or using a service such as CloudFlare he will need to upgrade to a modern version of UBB.threads as these are all modern features that are not supported on his 10 year old version, as mentioned previously.