So you installed the Live CD installer on a running Feisty system? I'm not sure that's supported :)
Anyway, the crash seems to result from nfsresize --info trying to analyse an NTFS partition that has already been mounted. Do you get the same problem running a Live CD on that system?
ntfsresize v1.13.1 (libntfs 9:0:0)
ntfsresize: ERROR: Device '/dev/sda1' is mounted read-write. You must 'umount' it first.
partman: Error running 'ntfsresize --info'
"installed ubiquity in Feisty and started it..."
So you installed the Live CD installer on a running Feisty system? I'm not sure that's supported :)
Anyway, the crash seems to result from nfsresize --info trying to analyse an NTFS partition that has already been mounted. Do you get the same problem running a Live CD on that system?
ntfsresize v1.13.1 (libntfs 9:0:0)
ntfsresize: ERROR: Device '/dev/sda1' is mounted read-write. You must 'umount' it first.
partman: Error running 'ntfsresize --info'