This might help
For everyone who has problems or doesn't know how to unpack z01, z02, files, follow this simple procedure: open only the zip files (ignore z01, z02 etc...), select the content and extract somewhere. That's all.
But ALL music files have added .001 or .002 or .003 or .004. If only one of them was left with .7z then it wouldn't be problem - I think.