Thanks for writing in with your question. We have a variety of ways to run our Email Preview tests, and it sounds like right now you’re using our recommended Autoprocess method.
We’ve noticed that there are a number of email service providers that do not accept the ‘+’ symbol in email addresses, and created the ‘.’ option to enable you to continue running tests.
We also have a Webinar if you’d like to watch it, it may help you navigate using our system with a little more ease! You can find that here: http://vimeo.com/106499517
If you find that you’re still having issues with your email preview results populating, please write in to us at support[at]emailonacid.com and we will dig deeper to find the culprit as soon as possible.