This plugin was made to show google weather info on wordpress. It was designed to fit the needs of a customer of virtual2.
For that to work you must have the plugin qTranslate installed and enabled. The GoogleWeather4WP plugin detect's the selected language in qTranslate and tries to show acording it.
The default language acts if the qTranslate plugin is not installed, or if it cannot detect the used language by qTranslate.
Yes, you can. Just head with ftp or file manager to wp-content/plugins/google-weather-4-wp/imgs/ and replate the images. Dont forget to mantain the icons names.
No. That is not a bug. For the widget title to change acording to qTranslate language, you must make it this way: [:en]widget title in en[:fr]widget de titre en fr[:XX]widget title in XX language if you type that in the widget title in the widget configuration, qTranslate will make it availiable in the defined languages.