I write this message, because I have translate your plugin in the French language, if you are interested, you can integrate it directly into your plugin during an update to facilitate its access to the French speakers.
The link of download of the translated files : http://www.tradpress.fr/trads/wordpress-importer-FR.rar
You can make a link to my website : http://www.tradpress.fr
I would be grateful to you for it,
Best regards. ;)