Hay,

I've updated my earlier post in AT+ to now include the file size limits and other facts of the various ways to upload images.

Generally there is a 3MB size limit across the site. I've tried to upload a 2MB image using the Editor and it automatically resized it to something like 30Kb and the 800x600 dimension.

It's always a good idea to upload small file size images as it will speed up the process.

I also prefer to have the images uploaded instead of linked to. It's quite possible that the other host may not exist in the future and your pictures become unavailable and vanish from AT+.  But you can still link to outside images if you wish.