>Is there a guide how to fix missing translations in TDE 14 for 
>German?

None that I am aware. For a long while I've wanted us to post a how-
to on the wiki to address the topic. For now, probably a good 
starting point is the KBabel handbook (tdesdk). If you get started 
on this I'll help massage your notes into some kind of how-to.

Darrell