Following discussion on irc, we're now waiting for Canada to come online so that Frank can explain how he has his sapi installations working without using PATH..
(in which case Edin's right - but what do the majority of new users install? cgi or sapi?)
Here is the code which generates the Windows installer code:
http://cvs.php.net/co.php/php-src/win32/installer/gen-nsis.php
Goba