Thank you for writing.
Directly to your questions.
1. There is no built-in functionality to export all settings from the RadPropertyGrid. You will have to implement it on your own. This should not be very difficult as you have access to all the PropertyGridItems, which represent properties of the edited object through the RadPropertyGrid.Items property. You can iterate and save all values to an xml for example. Then you can restore them by reading them form the saved xml and setting then through the same items collection.
2. There is no problem to set an object form a parent, child or any other form to the RadPropertyGrid. You just have to do it through code and not through the designer.
3. To set an object as selected for the RadPropertyGrid using code, you should use the SelectedObject property. You an also set a collection of objects as selected using the SelectedObjects property.
I hope this will be useful for you. Should you have further questions, I would be glad to help.
the Telerik team