Hello Artur,
1. We discovered problem with Content Manager when revisions are used. This sometimes cause content elements to break. Did you use Revisions?
2. Which version of the Content Manager you have? We fixed few issues that was causing strange behaviors so please update it (Appearance->Install plugins)
3. Unfortunately adding icons for Translated menus are currently not available because of way how WPML handles menus. But you can always add menus custom class and add background image with few lines of CSS
Vladimir
