Somehow your browser doesn’t retrieve config.xml from the Firefly server. Would you be able to check the permissions on and the existence of config.xml in the admin-root directory on your NSLU2?
The config.html page will make 3 calls to the server when the page loads. Each call will result in 2 ActiveXObject errors. (6 errors in total for a successful config.html load)
The html snipped you get is just what is on the page before the script writes the config stuff into it.