This multilingual site is born around 2 years ago (with theme TwentyEleven) to demonstrate as Twentyten-xili, how to use example child twentytwelve-xili. Since lot of improvements in WP Core and versions of xili-language plugin…
Example child theme twentytwelve-xili is downloadable now in version 2.0 and uses recent technic (classes and more…). He is also compatible 3.5+. Technical infos are here on website showing twentythirteen-xili.
Here posts and how to are are left in place as learning. The posts about gallery (jetpack) and floom slideshow remain valid.
So remember to read the date of the article and the versions !! Visit also wiki