Checkout Not Processing Orders

-- url of the page with the problem -- : XXX
-- HikaShop version -- : HikaShop Essential: 2.3.0
-- Joomla version -- : 2.5.17
-- PHP version -- : 5.4
-- Browser(s) name and version -- : Chrome 34.0.1847.116
-- Error-message(debug-mod must be tuned on) -- : N/A

We have two methods of ordering two separate products. One of these methods is through our "registered" users only area, and I'm having no problems with that process. User logs in, adds product to cart, and purchases. Order creation and notification e-mails are sent fine. They payment method is collect on delivery which we've modified to look like an invoice.

The other method is available to the public and I've set it up as a guest checkout. The payment method is via credit card through payjunction. When you visit the URL above, click the "Sign Up Today" button and go through the checkout process, it hangs up at each step in the checkout.

First after entering my billing address and click "Next" it goes to a strange page with no css (see attached). If I click the "Payment" link to move on to the next step I fill out my CC info, click the "Process Order" button, then I'm taken to a completely blank page. The credit card is charged, but there is no confirmation page and there are no confirmation or notification e-mails sent. We do receive a payjunction payment notification email however. If I refresh this blank page I'm kicked back out to the last step and if I try to enter my payment information again I'm told it is a duplicate transaction and denied.

I'm confused as to why one of my checkout processes is working just fine and the other is not. Any help you can offer is greatly appreciated. Thanks!

I'm using all of the test credit card and test payjunction information to try and do this. Here are the required fields for a credit card order if you want to try and test yourself:
Address: 8320
Zip: 85284
Card Number: 4444333322221111
Exp: 01/15
CVC: 999

To clarify, the order is being processed and it appears in the backend. The front-end display to the user is where the problem lies.

I sincerely apologize, there was an error found in some PHP code that was inserted. Please disregard this post.