xwiki don't understand xwiki syntax 2.0

I want to force users to use xwiki 2.0 syntax. In order to do that I modified some files :

xwiki.cfg :
xwiki.rendering.syntaxes = xwiki/2.0, xwiki/1.0

xwiki.properties :
core.defaultDocumentSyntax = xwiki/2.0

In order to test it, I edited an article in Wiki and I wrote in it : = Title =. When I viewed this article, I didn't have a title but I had as content : = Title =.

When I wrote 1 Title, I had a real title style as content of the article.

Another problem : with the configuration :

xwiki.cfg :
xwiki.rendering.syntaxes = xwiki/2.0

xwiki.properties :
core.defaultDocumentSyntax = xwiki/2.0

, I can't access anymore to the form allowing us to create new panels. Instead I have something like #include(#Panels....").