You can now block them without setting your folders to "NSFW". There's an option in each folder to "block rips".
Go to "My" (on the top bar, next to "Home") - then select "Photos", then there's a list of your folders on the left. Select the folder of images you want to change options for - I think you may be able to do this only one folder at a time, not one image at a time, but check - and click on it.
Then click "album options", click the box that says "block rips", and click OK.
