OM problem when loading session with pictures on whiteboard

[Mathias Bässler]

Hello,
 
I stumbled upon the following problem: When I drag two or more pictures into 
the whiteboard everything works as it should, pictures are draggable, resizable 
etc.
Then I leave the room and enter it again. Now my pictures are still loaded into 
the whiteboard. When I try to select a picture the last picture I dragged into 
the whiteboard before leaving is selected, no matter which picture I click. I 
can only select and drag, resize,... this last picture. If I delete it and try 
to select a remaining picture, everything freezes/crashes. I was trying to fix 
this, but I don't know where I have to look...
Could you tell me which files/methods are involved when loading a saved session?
 
Thanks in advance