Please read for an updated status on RailsCasts:
Learn more or hide this
GitHub User: skills4ever
I figured the problem (or at least the issue that I was experiencing). It had to do with CSRF and how Ruby on Rails handle HTTP Post. I initially followed a tutorial on Braintree where it used regular html form. . This caused Rails to loose the session because of security associated with CSRF. To pass Rails's security check, I had to use <%= form_for @myobject, ... } do |f| %>. Lesson learned.
@FabricioFlores, have you been able to address the filter chain halted issue. I am having the same problem. What is the fix?