Thanks guys. It is working as it should now Next step is to look at the Cloudfront and get that up and running.
I found a guide but when creating a distribution I am wondering how to manage the fact my forum is not located in the home directory of my server. i.e. Should I state /forum when setting up the distribution or is this irrelevant.
I ask because when I created /forum under the distribution, and then pasted the created AWS Domain into IPB, the forum lost all images.