I actually just found the solution.
In the php page code I found the following excerpt from the $WA_fieldValuesStr statement:
((isset($_POST["active"]))?$_POST["active"]:"")
and changed it to this:
((isset($_POST["active"]))?$_POST["active"]:"0")
I presume I should probably delete the quotes around the 0, as it should be a number, not text; but it does work. . .