[CentOS] USB install annoyances

I tried to boot from my 6.0 USB key, no joy. Updated it to 6.2. Still no
joy: it gets started, I do the disk layout, it formats the drives, and
then fails, saying that it can't find "image# 1". Over in the log, I see a
lot of it not finding any drive at all, yet all the h/d drives and sda2,
which is what the USB key is, and where the linux partition is, are
mounted.

Guys, any idea what "image# 1" is, or what configuration file is telling
it to look in a wrong place?

Thanks in advance.

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