Yes I do already for Turkish. I did not yet bother for German. But then the 60Cx can display Ü and Ö. Or not rotated?
At second thougth: If in utf8 the Turkish ö is coded with the same byte values as the German ö (and i think that will be the case) then if translit keeps the tables per area then the transliteration could be different. But i think that in short i will do away all areas (the .gpx files) and only use one transliterationtable for the whole world as i do now already for the 's.