*.astd
*.dncg
*.fchunk
*.pck
They also have the same header "CHNK".
I checked out some files in "/media". There we have *.fchunk files which contains lua-scripts. I found many filenames in these files, e.g. in ScriptsLuaScripts.fchunk:

So it should be a lot easier to unpack these files. Can someone have look?
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Thanks.
