"We aren't going to allow suggestive or "censored" words,
blots or blurs." 
OK I understand that bit. 
"The thumbnail should be an accurate representation of the image
you've posted."
OK I, also, understand that bit.
So you are not allowed to use the content of the picture if it is a nude figure. Because a true thunbnail should be simply a small version of the main picture. But that isn't allowed. OK And I'm not allowed to do a thumbnail that has any blots, blurs, smudges or any other form of action painting oh and no words that may be considered suggestive or rude or naughty OK. 
Thank god I don't do nude photography.