Please note, you do not need to delete an operator to remove them from a room. You only need to de-select them from in the list.
In either the Add Room Form or the Edit Room Form, select the Operator you want to Edit, click the Edit Operator button, next to the Operator List.
In the Edit Operator Form, click the Delete button.
The Delete Operator dialog asks for confirmation to delete the Operator. Click Yes to continue.
The Operator Deleted dialog will confirm that the Operator has been successfully deleted from the system.