In addition to the previously reported problems, I found an issue while trying to create forms for some sites I have in production and ran into another issue.
It is adding the words "null undefined" right after it puts the includes at the top of the page. So, on my page, I get this at the top after running form builder:
<?php require_once("webassist/form_validations/wavt_scripts_php.php"); ?>
<?php require_once("webassist/form_validations/wavt_validatedform_php.php"); ?>
undefined<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">