Your nav drive is currently on V24.1 and you certainly can do the upgrade to V26, which will take you to the latest version of 4-1/60. This will give you the latest graphics and features.
It will have no impact on the language pack. You have to have the vehicle/nav drive recoded at the dealer in order to change that.
http://www.xoutpost.com/navigation/94...ystem-faq.html