The error "No init found" usually assoicate root file system is to setup incorrect, your root file system should have /sbin/init, so said your kernel command line parameter "root=sdb1" than if you take your sdb to a pc mount it on /mnt, you should see /mnt/sbin/init. otherwise you should try to rebuild your root file system.
I tried to use the files in the Dreamplug repository but I could not get it to work. This is what I did:
1) formatted a USB drive with a fat partition and an ext2 partition
2) copied the uImage file into the fat partition
3) copied the files from the dreeamplug_rootfs archive into the ext2 partition
4) changed uboot to fatload the uImage from the usb stick
5) changed uboot to boot from the usb drives ext2 partition
Booting starts but ends with a kernel panic that says:
Kernel panic - not syncing: No init found. Try passing init= option to kernel.
Does anyone know what might be wrong? Thanks for any help.