Some people can find just about anything sexual. Take me, for example. Assuming I don't have to censor the words anymore (this better not change back to needing to censor them again), what I find sexual are people wearing clothes as opposed to them without clothes on (unless it's deliberately sexual...like adult material if you know what I mean).
Non-sexual nudity is just that...nudity without sex. The words are pretty much self-explanatory. The problem is most people can't tell the difference between nudity and sex, so they fuse them together with the old belief: "nudity=sex". I used to be like that before I discovered naturism. You might say naturism cured me from the old "nudity=sex" belief.
In regards to non-sexual nudity with children, pedophiles won't care if children are nude or wearing full clothing. They will see sex with children, regardless of what they wear or don't wear. Any movie that has children in it could be a pedophile's dream. Just something to consider.