Hi Timo,
The translation is finished 🙂. Just a quick note: the correct label for the language is "Galego" (not "Gallego"). Language Code: gl or gl_ES. However, if that is the system's naming convention, you can leave it as it is.
Regarding the language selector, Galician (Spain) does not appear on my Mac. Catalan (Spain) does appear. My Mac runs Sequoia 15.7.4 (24G517).
Can I access the translation in the app now, or do you still need to make some UI/backend adjustments?