more mess on installing arch linux on chromebook11

Since it completely mess up when I installed xorg on my arch, I decided to do whole installation of arch linux again.
I rerun the install.sh but this time installation of arch linux is failed. When I run install.sh prompt said
cp: cannot stat 'root/boot/boot.scr.uimg': No such file or directory
Actually there are no boot.scr.uimg in /tmp/root/boot/boot.scr.uimg.
This is weird because last time install.sh run without problem and boot.scr.uimg should be extracted from ArchLinuxARM-chromebook-latest.tar.gz. Similar issue posted on arch linux arm