Uploads seem to be working for me. Can you take a screenshot of the security error you get so I can see it, and email it to me here: johng at forumfoundry.com
I get a message saying 'security error occurred. Please press back, refresh the page and try again.' I have done this several times and keep getting the same msg. I have also tried on three devices (phone, laptop and tablet) - phone and laptop keep just trying with no outcome, and I get the security msg on the tablet. The photo is a png. file.