Which model year is your car? If I look at the current CLK from
http://www.mercedes-benz.de/content/...pe/prices.html
I can only find an Audio 50 APS CD Navi? The Comand APS of the current CLK seems to be a DVD version.
On the other hand if I look at the Navi discs from:
http://mb-accessories.net/mba/mba_we...b2b64b&cmdl=13
I cannot find any Navi DVD but a CD even for the Comand.
The part number B6 782 3589 is shown for the current Audio 50 APS anyway, but the version is indicated as 6.0. Perhaps the site is not exactly up-to-date.
Browsing the site on different languages does not change the part numbers, I tend to remember that the W211 discs for an Audio 50 APS had all supported languages on each disc, two discs in the set, each covering "half" of the Europe. Also my W221 Comand supports all major European languages, I doubt MB has support for any other languages. I cannot be sure but I would bet you would get both English and Spanish on a new DVD or a new set of CDs.
PS. I'm not native English speaking myself but we've been well accepted here. And your question was easier to understand than some questions from native English speaking persons :-)