Attached syslog with the correct script traced as you specified. This time I tried 10GB HDD instead of 12GB, it appeared again, the number seemed very similar to the one in screenshot (1999 ... I did not actually check all the digits, but guess it was the same). Also this time I attached the syslog right after the dialog appears, but before hitting any button on it (like "Go Back" or "Continue").
Attached syslog with the correct script traced as you specified. This time I tried 10GB HDD instead of 12GB, it appeared again, the number seemed very similar to the one in screenshot (1999 ... I did not actually check all the digits, but guess it was the same). Also this time I attached the syslog right after the dialog appears, but before hitting any button on it (like "Go Back" or "Continue").