we had to change the default gallery but keeping the same name "default"
actually you can use the old gallery with the template "default old" ( which is using simpleviewer and flash to display the photos
here a video to see how to change back the template to simpleviewer default
[video=youtube;Yo-GVszWa1M]http://www.youtube.com/watch?v=Yo-GVszWa1M[/video]