I changed my mind during the operation and thought 620 px wide was enough so I re-uploaded via FTP the original backuped files slideshow.css and standard.css to replace the files I was editing.
Since then, when I insert a gallery on a page using gallery model template page, the gallery is placed at the bottom-left of the page and doesn't display the image. (when using default model, the gallery is well placed but doesn't display images as well)
I deleted the theme, deleted my wordpress, reinstalled wordpress and theme and still have the same problem: http://georgesfrances.fr/paysages/
Do you have any clue where the problem comes from?
I can tell those are not the latest files and/or a legitimate copy. Please download the files from ThemeForest and re-install the theme. If you continue having problems, let me know.
yes I was trying with shortcodes ... now i used the gallery edition window. it's allright but I have thumbnails under the gallery, as you can see on this page :