I've changed the language to German but how do I get umlauts
a) Change your keyboard layout to German in Regional Settings. The umlauted
letters are then where ', ;, and [ are on a standard UK keyboard (uncertain
about USA) (ß is where - is)
or b) Use Insert > Symbol
or c) Memorise the character codes. To get ü for example, hold down Alt and
tap 0252 on your numeric keypad, then release Alt. 0223 is ß, 0246 is ö,
and 0228 is ä. I'm not sure about the capitals, but you can look them up
using Character Map.