Ok, this book - wtf. How did you find it?
About the banning, I reckon it would be ok, although considered extremely bad taste. I can't imagine a publisher taking the risk. However, it's forbidden to use the swastika at all, in any context (1), so the image on the title page would have to be changed. The book is also not shown in the German Amazon search. (Yes, I'm German.) Sounds very interesting though!
(1)(there have been left groups with emblems with a crossed-out swastika having problems in court for this)
Don't be too disturbed by the weird imaginings. If they're particularly weird you could probably write a modestly successful Bizarro genre story. (In my favorites is http://www.amazon.com/Ass-Goblins-Auschwitz-Cameron-Pierce/d... which may be banned in Germany.)
A quote: "We don't have thoughts, we are thoughts. Thoughts are not responsible for the machinery that happens to think them." --John K Clark.