You just need the one include: webassist/email/WA_Email.php
The others should be removed.
You can turn on debugging with smtp and that will give you information about when and why it is failing.
Authenticated SMTP often won't send email FROM someone other than the logged in sender.
Most likely the FROM has to be set to the same value as the $Email->Username and then you can set the ReplyTo from the form value.