can't find display controls, synaptic broken filter is broken.

[Capricorny]

You should (from somewhere else) try

sudo e2fsck -fy KNOPPIX/knoppix-data.img

and look at the output.
If you regularly find that it is left in a broken state upon normal shutdown, that is very interesting news, I would like you to post about it in this subforum!
Good luck!

"Somewhere else" here means that you should (of course) NOT try to check/fix a mounted file system, i.e. do it from within a Knoppix session using that persistent store. In practice, you can also do it from within Knoppix though, starting it without mounting persistent image (cheatcode "noimage"). And if the file system of the persistent image is broken, you may have to start without it. After fixing, it may (in my experience will ofte) work correctly again, but there is no guarantee.