You can use a custom picture of your own creation if you wish, but only people who have a copy of that graphic will be able to see it. Everyone else will see a black background. The person will be kept out for the remainder of their session, or until ownership is transferred. They can get around this by logging off. If everybody inside leaves, the room automatically opens.
Scripts are on by default.
Same as 'rhide off. A member room will disappear from the Palace site if it empties out while its owner is logged off. If the room remains occupied, its owner may log off and log back on, and will retain ownership of the room. Member rooms all disappear when the server goes down. Each member is allowed to create only one member room at a time.