when a page displays blank, it means a php error has occurred but error reporting is turned off.
add this code to line 1 to turn error reporting o:
most likely the problem with the verification link is the WAGLOBAL_Root_URL. this needs to be set to the root of the user registration files on your site.
so for example, if you get to the login page using the URL:
the root url needs to be:
$WAGLOBAL_Root_URL = "http://www.mydomain.com/userRegistration/" ;