Proofing File Never Loads


We decided to experiment with proofing to see if it might meet a need for our organization. I setup a blank sheet, enabled proofing, and added a single proof by clicking in the proof column and uploading a 4MB PDF. The file uploaded, but the display just shows the spinning loading icon... which never goes away.

I tried using the Request Feedback button to send an email, which worked, but the resulting link (in the email) took me to another screen with the same loading issues.

I opened a support ticket, but thought I would post the issue here as well just in case anyone had any ideas. It seems like a great feature if we can get it to work.

I have attached screenshots below.