Umm but the kernel has correctly detected the Toshiba by itself. I don't know why you get the multiple lines, but I have seen that before and it seems normal.

I haven't done a drive builder to install a new drive but the fact that the kernel can't find a root fs is probably more the reason you are getting the "No hard disk found" message. This points more to a disk builder problem. Are you sure you're doing the disk builder bit right? Disk builder will not install the player software etc. The drive has to be the master to get the player software while doing an upgrade using the correct .upgrade file. This would explain why it falls over on the single drive boot.

You are powering off the empeg and waiting until the disk builder program tells you to power on aren't you?