Actual I don't know what the problem is to find some files in a *.zip file that would be unzipped into a ..\ctp2_data\english\gamedata\ folder, so that you can only copy these files into the ..\ctp2_data\german\gamedata\ folder.
Another way of doing this would be to copy all the files in the one folder to the other folder and when you are asked if you like overwrite a file to press the no button. Well this works only if you install a mod and not an update that overwrites some of the files of the mod itsself. By the way all mods for ModSwapper do have a prefix lilke: XXX_
Well and if you can't bear the mishmash of German and English you can still use Sir Ralph's method, but you don't need to ask anyone to send you the files, you can download them from
this thread.
-Martin