Suggesting but not recommending:
1. How about re-mounting knoppix-data.img as readonly.
2. Then creating new Union with KNOPPIX and directly compressing the new Union.
I think this procedure can be scripted.
might be interesting to divide the script into a further function:
1) rsync of Unions
2) generate the compressed filesystem
3) write to USB
Between the first and second feature I'd like to manually edit some files or folders in case I notice that you have a problem ....
Stupid silly example:
I customized the splash screeen Compiz (splash_backgroung.png & splash_logo.png) with my logo
I have placed in / KNOPPIX-DATA/usr/share/compiz and then I updated the path to two files in CompizConfig.
Well, by mistake the name of the file that I used had two capital letters than the original ....
result is that the new recombined Knoppix filesystem I found both the original file and my files ... and so I lost the customization ...
In order to fix the problem I should start all over again by launching the script again ... with a huge waste of time
Using your flash disk Installation with persistent memory you shall not edit '/KNOPPIX-DATA/'!
In your "silly example" write your modifications to '/usr/share/compiz' not to '/KNOPPIX-DATA/usr/share/compiz' and use this path in CompizConfig.
And before "recombine" Knoppix test your flash disk Installation as long as there are no errors.
Greetings Werner * http://www.wp-schulz.de/knoppix/summary.html
Own Rescue-CD (Knoppix V6.7.1 remaster).

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