I'm late to this post but when I google nw.dll this is my first result.
I was also wondering why nw.dll was so big. I don't see why we don't just leave it compressed?
I downloaded UPX from sourceforge then put nw.dll in the same folder, from CMD upx -9 -qvfk -o nw1.dll nw.dll then rename nw1.dll back to nw.dll
It takes the file size down from 62MB to 21MB. My game seems to work fine with the compressed nw.dll. My total game size is now about 71MB. Anyway use it ,lose it, would be interested to know is someone has compressed it more or if it causes problems