While I have been a member of Picnik for several years, its only been in recent months that I have used its photo-editing feature on a regular basis.
In attempts to move my projects along more quickly after uploading an image to Ipernity from my computer, if necessary, I would then upload the image to Picnik from Ipernity, crop and/or straighten it, as needed. And then click the REPLACE tab.
Not until today did I learn that these particular RELACED images, edited with Picnik, can not be downloaded.
So, may I suggest that you ... use Picnik with caution!
Since I have several photo-editing software on my computer ... I wish that I had realzed this before today.