The image is from http://ftp.nl.debian.org/debian/dists/testing/main/installer-i386/current/images/netboot/. I got there from http://www.debian.org/distrib/netinst#netboot. The testing and stable images are both the same (unstable is different; it doesn't work either, but that's a different issue). Scrolling through the installer syslog, I found "Oct 22 16:42:27 finish-install: warning: /usr/lib/finish-install.d/06user-setup returned error code 2"
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