2. The default demo language links doesn’t work, it’s just an option to show that you can create multilingual site. If you plan to create multilanguage site you may use WPML plugin https://wpml.org/documentation/related-projects/woocommerce-multilingual/, but if you want to simply translate site to one language I would recommend you use Loco translate plugin http://xstore.helpscoutdocs.com/article/30-base-theme-translation (the same for woopress theme).
3. Please add this code in Theme Options > Custom css:
.top-links {
overflow: visible !important;
}
Regards