Guys,
I had initiated the UNC application a few weeks back. Looking at the online app, I had assumed that you need to submit $135 before you schedule your interview. But a few minutes back, I was able to schedule without making the payment. I am myself confused as to how this happened. I filled in all the information in Part 1 and submitted part 1. For submission, it does not mandate making the payment. After submission, I came to the payment screen, and here I clicked "Pay by Credit Card" button, after which I came to the authentication screen. Here I clicked the browser back button. I thought, I will call them tomorrow and confirm whether the payment is really required. Before logging out, I thought what the heck, let me just try click the Interview link. I clicked it and voila ! I was able to schedule. I got a confirmation email too.
Now I don't know whether this is a bug in their online app, or the way the application is structured, it appears misleading that you need to make the payment. Anyhow, I will be calling the Admissions office and confirming my position.
Ranjit