In the Addons > Image Content you have the ability to mount both image + content. If you mount a image in this addon and then right click on the image (the image must be uploaded), then go to Border Radius, this does not work in this Addon, you could insert what value you want and the radius will not work, so no curves appear on the image.
Please replicate this and if you get the same result, log this to the bug list, if not the same result, please clarify how you resolve radius on the image when using this addon.