This didn't work for me.
The solution described using the alternate install was done and the system was installed but, since my user directory was encrypted in /home/username/.Private using encryptfs, it failed to mount, and I didn't find a workaround yet, since no username nor any passwork seems to work, even typing the exact terms I entered during install. So I can only access a Guest account, which dosn't allow me to access any Terminal nor sudo neither any graphical interface that requires root.
It seems that alternate install doesn't have the necessary packages to deal with encryptfs, since it doesn't understands its partition type. I tried to get into recovery other times to try to figure out something in the fstab, but nothing works. Even adding /home/username/.Private /home/username encryptfs defaults 0 0 makes the installed system to tells me it is not a valid partition.
Maybe you should advise people, by editing the thread, not to try this in this case, or sugesting a workaround, that maybe would be copying no only cryptfs but also fstab, or maybe installing other packages. All I know is that more people is having a hard time with this thing, and in times when ubuntu wants to go to the crowd, in cell phones, things like these shouldn't happen anymore. The closer canonical gets from people willing to pay for it, the least it can just rely in the "use it in an 'as is' basis" clause.