Hi ragalthar
This is a guide for you or anyone else who wants to use German or other languages that don't appear in the normal firmware:
Firstly I flashed the R1GA030 BALTIC FS and MAIN
Next edited Customize.xml to accept DE and EN languages:
<allowed-language>en</allowed-language>
<allowed-language>de</allowed-language>
and uploaded to tpa/preset/custom
Finally I uploaded the W995 language files/T9 for de and en to tpa/system/language , and turned on the phone...everything works, now have W715 with German !!! :D :D

(you need de.lng, de.t9, en.lng, en.t9)