We have some methods that allow you to remove an instance from the dashboard.
1. The remove function can be invoked via the revealcloud collector, so for example when your instance is shutting down you can add the following command "/usr/local/revealcloud/revealcloud -R"; and the system will be removed.
2. The other method is via our REST API (see http://dev.copperegg.com/revealcloud/systems.html the "remove" paragraph)
3. We also have a hide option:
"curl -u APIKEY:U -XPOST https://api.copperegg.com/v2/revealcloud/uuids/<youruuid>/hide.json"