AFS Widgets uses Ajax to refresh its different components. The use of this technology makes loads smoother and faster.
But one restriction of Ajax is that it is not allowed to query other domains than the original one.
If the Search, ACP, Click or any other service is hosted behind an other domain than the one of the web server, a reverse proxy has to be configured on your web server.
See following topics for more information, and examples to set up reverse proxy on most frequent web servers: Lighttpd and Apache.