Wow, that's so cool that you're able to practice your German with the game! Wünsche dir weiter viel Erfolg mit dem Lernen! :)
Thanks for pointing out the bugs, I'll try to fix them for the next update. The Ecclesia is in the western part of Caelum, head to the place with the little fountain on the upper half of the map and go up to the stairs to the next area. It's the big church-like building :)