You should first install the file nl2000_v2.zip. Unzip the contents of the zipfile to a temp folder and then run the installer.
After you have installed v2, unzip the contents of nl2000u2 to a temp folder and install the update over the scenery you just installed.
If you get errors during one of the two installs, please consult that FAQ on the site on how to do a manual install.
Success with your install

,
Arno