I have uncovered part of the problem with folks getting blocked from the site.
Long story short - our host implemented some draconian security features which resulted in IPs being blocked. I am doing battle with them over these, but in the meantime, I can ask for IPs to be whitelisted.
Please PM you IP where you are getting a server not responding, of forbidden error messages, and I will have it whitelisted.
Longer story if you are interested - About once every 1-2 months we get slammed by some spider or robot, which spikes our usage and crashes the site. I then reboot the site and block that IP. Our host was pressuring me to upgrade our server package to allow for these occasional spikes in usage. I was like, I'm not going to pay a couple hundred dollars a year just so robots and spiders can fuck with our site; I can live with the site going down once every month or two in the middle of the night. They didn't like that answer, so changed settings and security rules which will block IPs that make "too many" requests in "too short" a period of time - like if you open several tabs quickly, or even do a search that returns "too many" results.