Board Thread:Support Requests - Getting Technical/@comment-5175866-20150120155225/@comment-4189499-20150120180858

Have you tried uploading the image using either the source editor or RTE to see if there's any difference? I generally find it's easier to make these sorts of things work in source editor. It would also be a good way to see if it's a problem with Wikia as a whole or just the VisualEditor.