Based on other similar reports, I believe that this is essentially a nUbuntu bug. They don't preinstall the console-setup package on the live CD, which Ubiquity needs. Please report this to them if they don't have a more recent version available.
Based on other similar reports, I believe that this is essentially a nUbuntu bug. They don't preinstall the console-setup package on the live CD, which Ubiquity needs. Please report this to them if they don't have a more recent version available.