I’ve as first cut of a patch for v0.12:
You’ll need to download and unpack v0.12 of the game first of course. The patch is just translations, it can’t make your v0.11 game a v0.12 one! Follow the steps in the patch’s readme and you should be good.
Save games from v0.11 won’t work in v0.12 (in either language) so you will have to start a new game. I haven’t played through all the new content yet, so there might yet be issues.