Try changing:
<?php virtual("/WA_ValidationToolkit/WAVT_Scripts_PHP.php"); ?>
2 <?php virtual("/WA_ValidationToolkit/WAVT_ValidatedForm_PHP.php"); ?>
to:
<?php require_once("WA_ValidationToolkit/WAVT_Scripts_PHP.php"); ?>
2 <?php require_once("WA_ValidationToolkit/WAVT_ValidatedForm_PHP.php"); ?>
Dreamweaver will use virtual() instead of require_once() if the Create Links Relative To option is set to Site. Before running form builder, try changing that to Document,