As I've perused this site, I've noticed that whenever I try to download certain artworks, they appear as "blank.png" and the image downloaded is, as one might guess, blank.
Cut that shit out.
Seriously.
Anyone with half a brain and a modicum of technical knowledge can still download your art. It's called the "Print Screen" button. That + Photoshop + Ctrl+V = Anyone Who Wants Your Art Now Has Your Art.
It's like locking a screen door that already has an arm-sized hole in it: annoying at best. One must think "zomg, why would they bother to lock it?!"
You are the only one who has control over your art, and that is in how you distribute it: