I am having the exact same issue that was originally posted by d4vr0s. Has there been any updates to ADB (manually) or RSD the files over yet?
I have been working on trying to update JB manually (moto-fastboot.exe) and I no longer get errors but after the red M boot logo, I get a black screen only.
*I can boot into recovery
*I can reload from .zip
Nothing gets me past the M unfortunately.
I am in the process of getting 4.2.1 running in virtual box and grabbing my image off my phone so I can hopefully see what the problem is...