Comment 2 for bug 47046

Unfortunately that livecd session is no longer available but I will know, next time, what log files to attach.

However, I think (95%) I know what may have caused this problem. The partition I was installing onto had (or may have had) a previous amd64 test installation (probably Gentoo) and when Ubiquity tried to chroot into /target to complete the installation it could have crashed if any x86_64 binaries or libs were called. When I checked the partition after this failed attempt there was a lib -> lib64 link in / and I did use this machine for testing various 64 bit installs over the last year. When I reformatted that partition and tried again the Ubiquity installation succeeded and I could boot on that particular partition.

So perhaps there is not a problem with Ubiquity and this was simply operator error. However, maybe a check for unsuccessful execution when chroot'ing could provide a warning.