Basically what tends to happen when you get a "Failed to write config" message is that a file cannot be found; it's basically a 404 error thrown by the server after PHP has tried to call the file when it's being run as a CGI binary. Once it's run the file it doesn't re-run the file, so it doesn't spew a normal 404 error.
Shane, could you post me exactly what you're putting in as your paths?
