I don't know why it says 5MB but it will only post if less than 2MB. My latest post about how to post pictures can be found at
Cromwell sewing machine
ETA I think that I have posted more than 5MB per post, but I'm not able to check right now. I know the individual images have to be less than 2MB and that there is a limit of five images to a post.
Janey - Neat people never make the exciting discoveries I do.