I always used the plug-in menu. I used the 3D View only for fine adjustments for the positions.
I have positioned the visitor in a door. In 3D View I could look into the room but the photo was complete black. I discovered that when the nose of the visitor icon is within the room and the coordinates are within the wall the 3D View will not be black but the photo. I need to move the visitor into the room (mostly 3 or 4 mouse wheel ticks) to have a not black photo. To check the correct position I started a low pixel (320 x 180) rendering.
I have the 3D view always in a separate window occuping the full screen so starting from 3D View will be a little bit easier.