One: a direct link to the image is still required. The curators aren't going to go on a search through the millions of photos on sxc.hu to try and find your image. Everybody follows this rule, no exceptions.
Two: royalty-free images still have licenses, and just because sxc.hu is
mainly a royalty-free website doesn't mean you don't still need to check that written permission isn't required, or that a model release isn't required, or that the image author doesn't just want some recognition. If you take a closer look at most of the licenses on sxc.hu you'll notice that a direct link is required to use any image from their site. See point one.
Three: I wasn't confused. My comment to you about editing posts button is to avoid spam. It makes it very confusing to follow which card is exactly the one we're supposed to be looking at if we have to hunt for it. Just 'Modify' the original post to update the card image. Also, anytime a post to this thread is made, everybody who's previously posted is notified. If you 'Modify' it doesn't do that. It's just polite