Customize Agent Update Messages

There are "Agent Message Overrides" in System Update Agent settings - but I wonder how to customize the german localization of these messages. And is there a way to customize the captions of buttons?

Here (reboot required message):

the "Jetzt" ("Now") makes no sense. It gives users the impression that by clicking a reboot will be done "now" - which is not true if reboot was disabled. It should be "OK" or something like "Verstanden!" ("Understood!").

In ZCC there are only english messages to customize, even if ZCC's language is German: