Found a solution: The problems is K2. k2.php was not correct coded.
See plugins/system/k2.php - specifically this code section:
if (JString::strpos($response, 'prefix="og: http://ogp.me/ns#"') === false)
{
$searches[] = '';
$replacements[] = 'http://ogp.me/ns#" ';
$replacements[] = 'http://ogp.me/ns#">';
}
Change this to:
$app =& JFactory::getApplication();
if ($app->isSite()){
if (JString::strpos($response, 'prefix="og: http://ogp.me/ns#"') === false)
{
$searches[] = '<html ';
$searches[] = '<html>';
$replacements[] = '<html prefix="og: http://ogp.me/ns#" ';
$replacements[] = '<html prefix="og: http://ogp.me/ns#">';
}
}
Thanks to "plethoradesign"
Now the editor appears but somehow all drop down box options are not clickable meaning you can't select a group nor templates and also you can't jump to the next step. Help is still needed. Best P