how do i unpack it? (sorry i have never done something like this)
Viewing post in How to mod/edit package.nw ?
Like I said, it's a normal zip archive - if you're on Windows, the simplest way would be to change the extension by renaming the file from package.nw to package.zip and using the built-in Windows Explorer to unpack it and go from there (just make sure to change it back to package.nw once you're done).
Alternatively, external tools like 7Zip shouldn't have a problem opening a .nw file.