Required File Upload Boxes

I'm having a problem with this form, and I'm hoping someone can look at it and help: http://www.viralfunnels.com/squeeze-page-order-form/

I have several required file upload boxes. I now have several submissions where people have left those boxes blank and it is still allowing them to submit the form. Is this a known issue?

Thank you for trying it out. I have one submission that only submitted something for the last of that series of 4 questions, and another that submitted for all of them except the first.

Both submissions also answered Yes to the question "Do you have a PowerPoint template you would like us to use?" and did not upload anything when the conditional "Upload it here" box displayed. That conditional box is set to be required, and when I do test submissions, it doesn't let me in either. Not sure how they managed to get through :)