[bepe]

I don't think you need PrefStats and most of the other stuff
Most of them are just statistics stuff that was used by UsabilityInitiative to collect data, like what menus the users are using the most.

For the editor just add the beginning to your LocalSettings.php and forget about the rest of it...
Like this:

# Some lines to add to LocalSettings.php to get these extensions up and running:

# Vector enhancements (CollapsibleTabs, SimpleSearch, EditWarning)
require_once( "$IP/extensions/UsabilityInitiative/Vector/Vector.php" );

# Vector enhancements config
# global: Enabled for everyone, users can't disable in preferences (FIXME this behavior should change)
# user: Disabled by default, users can enable in preferences
# Shown values are defaults
$wgVectorModules = array(
	'collapsibletabs' => array( 'global' => true, 'user' => false ), // Doesn't have a user pref
	'editwarning' => array( 'global' => false, 'user' => true ),
	'simplesearch' => array( 'global' => true, 'user' => false ), // Doesn't have a user pref
);
# To really enable SimpleSearch (FIXME)
$wgVectorUseSimpleSearch = true;

# WikiEditor (Toolbar, Toc, Preview, Highlight)
require_once( "$IP/extensions/UsabilityInitiative/WikiEditor/WikiEditor.php" );

# WikiEditor config
$wgWikiEditorModules = array(
	'highlight' => array( 'global' => false, 'user' => true ),
	'preview' => array( 'global' => false, 'user' => true ),
	'toc' => array( 'global' => false, 'user' => true ),
	'toolbar' => array( 'global' => false, 'user' => true ),
);