It seems that you're using an outdated browser. Some things may not work as they should (or don't work at all).
We suggest you upgrade newer and better browser like: Chrome, Firefox, Internet Explorer or Opera

if you own a physical german CD of the game, then you can simply overwrite the data in the gog gamefolder with all the data of the cd-rom. Afterwards you may reconfigure the setup but that's all it takes to switch the game manually to german language with all the german voiceovers and text.
I tried, but it somehow reverted the game to an earlier patch version. I thought it was not worth it.
Akariu: If the "issue" is meant to be that some of the spoken text is still in english....then that is it what I also have as an issue.
I don't know if my original cd just don't want to give me all the files needed or if it is just broken with this but I'm fine anyways because it isnt that much or anoying
I've had this problem recently, and I didn't really know why because I'd never had that before in all those years.
Now I've FINALLY found out what was the problem.

If you install the game from the original German CD under DOSBox, it somehow doesn't copy ALL the neccessary files to the hard drive.
In order to make it COMPLETELY German, here's what you need to do:

In the \DATA\ subfolder, you'll see that there are the following .RES files:

In order for you to have full German voice acting (not the occasional English voices), you'll also have to copy the
from the CD to the DATA folder on your hard drive!

Then everything's as it should be.

(Basically, I could upload the German files, so you all can turn your English version into the German one.
IF... that's allowed. ;) )
Well, you could upload them somewhere else and inform us ;)