hello,now I created an emmc image with the partition table information in your posts.I booted latest firmware in virtualbox but there is no network.
The GRUB bootloader in the WD firmware could not load the linux kernel ,so I used ubuntu GRUB2 and a modified grub.cfg.
The firmware seems working in virtualbox, and I can see serial outputs from the virtualbox,although lots of device not found.i got a root terminal and using ifconfig ican only see the bonding and loopback interface (there should be two more ,egiga0 and egiga1),
so I wonder how to fix the network problem
and contact me if anyone want these virtualbox images