I met this issue either. I have been blocked by this bug 747579 Ubiquity gets stuck at restoring previous packages Then I rebooted system after hours waiting. I tried the installation reported in 74579 again, then the ubi-usersetup occurred.
Then I tried to format my disk and try a fresh install. The ubi-usersetup still there. And in the end, the installation crashed.
I met this issue either. I have been blocked by this bug 747579 Ubiquity gets stuck at restoring previous packages Then I rebooted system after hours waiting. I tried the installation reported in 74579 again, then the ubi-usersetup occurred.
Then I tried to format my disk and try a fresh install. The ubi-usersetup still there. And in the end, the installation crashed.
My partition is
/boot ext4
/ Reiserfs
swap is seperate
The screen shot is in attachment