Warning: main(/MEMBERS/system/databases/mysql.class.php): failed to open stream: No such file or directory in w:wwwrootMEMBERSsystemlib-database.php on line 117

Fatal error: main(): Failed opening required '/MEMBERS/system/databases/mysql.class.php' (include_path='.;c:php4pear') in w:wwwrootMEMBERSsystemlib-database.php on line 117

http://www.geeklog.net/docs/install.html#failed-to-open

require_once( '/MEMBERS/config.php' );

$_CONF['path'] = '/MEMBERS/'; // should end in a slash

this path is correct
w:wwwrootMEMBERSsystemlib-database.php

and this path is too correct

You are not using an absolute path ... To quote from config.php:
bye, Dirk