Oh man Wardad. My brain just did the mental equivalent of a "double-take".
CS, the colony still belongs to the empire. You can still view the build que and facilities, you just can't build anything and you get no resource production. Any facilities with system wide abilities, space port, system grav shield, etc, still pperate as normal. You can drop population on it yourself, but your enemies cannot. They can destroy it fairly easily, or capture it in tactical combat, but not in strategic unfortunatly.
Geoschmo