Unibeast crash at "Cleaning Up"

I'm trying to make a Sierra Install USB with Unibeast (Clover UEFI, 16Gb USB, the OS in which I run Unibeast is Sierra 10.12.0).

It runs flawlessy until it reach "Cleaning Up" stage. It stays there for some time and then crashes with "exc_bad_access". What am I doing wrong? Thanks!