The error message from CloudFlare, if you read it, simply states that CloudFlare does not have a cached version of Stratics Forums. This is because forum content is too dynamic to cache. If you recall, we were having a lot of downtimes prior to using CloudFlare. In the past, this was occasionally due to DDoS, but more recently due to high memory usage or traffic volume. (Note: CloudFlare hinders the efficacy of DDoS incidents, among other things). In short, it's a server problem, not a CloudFlare problem.
I'll notify our SYSOP again about the issue, but they have not yet been able to pinpoint the problem.