I want to be able to repack a DS firmware that has been unpacked (with either Chism's tool or Loopy's tool - they both give the same output files, just different names). More specifically, I am trying to recompress parts 3, 4, and 5: Part 5 decrypted, decompressed is 239,520 bytes - MD5: 059B85E2FB02933CFE01533701024EB8. Part 5 decrypted, compressed is 63,928 bytes - MD5: 39CD298D25CA3E9587689F022EDC1536. I wont upload the files publicly as they are copyright to Nintendo. I have already tried recompressing and decompressing with all of the compressors from these tools: http://gbatemp.net/threads/nintendo-ds-gba-compressors.313278/ http://code.google.com/p/dsdecmp/ http://dl.dropbox.com/u/341300/Compressors/NL Compressor.zip But none of them can produce the original files. Does anyone know the exact compression format and could you provide a tool for this compression?