MODx can´t transform titles with accented characters into correct aliases. For example "Wörterbuch" should be transformed to "woerterbuch" (dictionary) not to "werterbuch". This is a real drawback for german websites and maybe websites in other languages, because you can´t let MODx create clean URLs.
As a german native speaker I would like to suggest some changes at the file manager/processores/save_content.processor.php.
'Ä' => 'ae',
'Ö' => 'oe',
'U' => 'ue',
'ä' => 'ae',
'ö' => 'oe',
'ü' => 'ue',
'ß' => 'sz',
Maybe there are some more corrections to do for other languages?
Mazso