Flash cm10.1 from ultimate rom

Hi all, I need help to flash cm 10.1 nightly or paranoid android from ultimate rom.
I've just flashed this:
http://forum.xda-developers.com/show....php?t=1927097
But I've not understood why I need it.
However, when I try to flash a cm 10.1 I have installation aborted status 7.
Help?!