Thanks again, utu!

You may need to look at the expanded contents of each element in a linux filesystem
to see what files might be over-written...
The list of all files in KNOPPIX1 is as follows,
Code:
.
./var
./var/run
./var/run/utmp
./var/lib
./var/lib/bluetooth
./var/lib/bluetooth/XX:XX:XX:XX:XX:XX              <-- MAC address removed.
./var/lib/bluetooth/XX:XX:XX:XX:XX:XX/settings     <-- MAC address removed.
./var/log
./var/log/wtmp
./.wh..wh.orph
./etc
./etc/modprobe.d
./etc/modprobe.d/snd-hda-intel.conf
./etc/localtime
./etc/default
./etc/default/keyboard
./etc/sysconfig
./etc/sysconfig/i18n
./etc/sysconfig/keyboard
./etc/environment
./etc/fstab
./etc/timezone
./etc/X11
./etc/X11/xorg.conf
./etc/adjtime         <-- LOCAL is substitued with UTC
./.wh..wh.aufs
./home
./home/knoppix
./home/knoppix/dummy_file
I am still puzzled by the misbehaviour of PCManFM caused by these files. The files, adjtime and dummy_file, are the only two foreign files and the rest created by booting the pc with "KNOPPIX 2 noimage lang=uk". If I understand the cheatcodes file correctly, KNOPPIX won't load the knoppix-data.img file when the noimage parameter is given even if the file is in the KNOPPIX folder. So, there shall not be any interference from the actual content of the .img file. To help myself to get the situation crystal clear, I have also tried to create the same set of files after the .img file being removed, and the result is still the same.

Such problems do do not occur with actual re-mastering...
Hope it's the case when I do my very first remastering...

Actually, the more I think about it, the more I see it as a "safety" feature so that I won't save something fishy on NTFS partitions by mistake while surfing the net so long as my imaginary safety feature won't trash the filesystem after the partitions are mounted manually.