I think that last time this kerfuffle came around, someone suggested that it could be possible to use a thumbnail generated from a slightly different (i.e., covered up) version of the image, as long as the slightly different image didn't look like it had a cheesy slapdash covering. In otherwords, I could have used an uncropped version of my "Naked Catgirl in a Temple with a Big Fish" where she was nearly naked, and had her naked in the main image. I was able to get a cropped thumbnail OK on that one though. (Except that it seems almost impossible to get a thumbnail down to 15K in size. I had to go with 100x100 pixels and the worst quality jpeg. Meh!)