In order to have the num lock automaticly on after booting the computer, I found out that in the lxdm.conf file the numlock has to be uncommented and set to 1. (unther the root /etc/xdg/lubuntu/lxdm)
So far no problem. When I try to save the changed document, I first get the question that it already exists and if I want to replace it, but when I say yes I get the message that he can't OPEN the document?!