I notified that each time I what to modify an event the image associated to this event was automatically erased. I think this is a bug because i do not what to re-upload the image each time I want to change something about my event.
Actually I saw it because I use to create the event, set all the fields, save it, check the view result, then I open it again and create recurrence for my event… but then, all of the recurrent events are image-less.
I tried the solution of the new image manager (wp 3.5) but the bug is still there :
http://www.e-dynamics.be/bbpress/topic.php?id=1860#post-7362
Thanks for the help Franky