I have setup a barebones install, and authenticated my bucket using the root user S3 credentials (just for now). Assets do not upload. I read a similar question here where the answer was that the response was being blocked by a firewall. I have tested on other connections and the issue wasn't resolved. Craft support suggested that I could edit some code on craft/app/lib/S3.PHP around line 771 but I'm not sure how to go about solving.