This is the log in your tarball, it is using mga but unfortunately with your xorg.conf, and it does not indicate any failure.
Can you please try again with a standard (or no) xorg.conf, and if it ends up with vesa, the mga log maybe Xorg.0.log.old
This is the log in your tarball, it is using mga but unfortunately with your xorg.conf, and it does not indicate any failure.
Can you please try again with a standard (or no) xorg.conf, and if it ends up with vesa, the mga log maybe Xorg.0.log.old