Thanks for this!
There's some error hidden inside the script - the uncompressed files are sometimes truncated. Take this archive: http://www12.zippyshare.com/v/xEGagmjn/file.htmlhttp://www12.zippyshare.com/v/DEibBgqw/file.html
First of all, the script finishes with an error. Then, there are three examples for truncated files, the ones I found after a quick check: 8e, bb and 40b. They contain cwav files, which have the full file size at offset 0xc. The last file is truncated in all of these examples.
BTW, yes, the music is included in the files with known compression so your script is perfect once it functions properly.
Thanks for taking another look!