Sorry kraket3...
For this language issue this will be fixed in the next release (including nightly builds/release candidates), however you should be able to fix yourself. If you edit default-constants.php in the WPS plugin folder, on the line that includes if ( !defined('WPS_TEXT_DOMAIN') ) change define('WPS_TEXT_DOMAIN', 'symposium'); to define('WPS_TEXT_DOMAIN', 'wp-symposium');
The styles is odd - do you maintain your own stylesheet for your site? If so, I suspect this is to do with not using the correct DIV ID/Classes that have been updated to use a more standard prefix. Alternatively, the new version of the wps.css (and minimized version) may be cached - do you use any caching plugins, and have you tried a hard browser refresh?
Finally - so we can keep all support in one place, would you mind using the WPS forum? We have a new support engineer (Robert) who monitors the forum, and you will get a much better response there so we can sort this out for you.