66087 - Hangs flushing cache end of first stage.

Revision 66087 hangs at the end of the first stage. The bar at the bottom the screen says "flushing cache".
I re-booted in debug mode and captured a debug log (see ergo-R66087-No1.log).

I then did a re-install capturing debug info, up to this hang (see ergo-R66087-instal2bsod.log).

Having killed Ros, I re-booted in debug mode capturing debug info through second stage, down to a re-boot and up again, until encountering a bsod (see ergo-R66087-2stage-reboot-bsod.log).

So what I have found is, that there is an hang at the end of the first stage of the installation, but Ros will next time boot into second stage and complete it. When booting the fully installed OS, at about the point of entering the desktop, it fails again.
I have had to enter commands on the receiving and not the test computer, though I was running in Debug mode and not RosDebug, which is not normal.