@riko with this error, it appears to be a software error on the target computer’s hard drive. Clonezilla and FOG uses the same disk cloning engine called partclone. I found this answer on the clonezilla site: http://drbl.org/faq/fine-print.php?path=./2_System/108_bitmap_free_count_err.faq#108_bitmap_free_count_err.faq
It says:
"You should make sure the file system integrity is OK before you save it as an image, i.e. the file system is unmounted cleanly. If you want to check and repair the file system, you can run “fsck” on GNU/Linux or ‘chkdsk /f’, ‘chkdsk /p /r’ on MS Windows. For GNU/Linux file system, e.g. ext4, reiserfs, you can also check option “-fsck-src-part-y” when you save an image. "