I filled it in too.
I thought the list of things which you may or may not find offensive was misleading because it included sexually explicit material without any descriptors. Whilst I don't tend to find any material offensive based of whether it is sexually explicit, I would if it appeared in an inappropriate context and I would if it involved harm - so bestiality, child porn, sexual violence causing harm. But if I ticked the sexually explicit material box if would look as if what I was objecting to was the fact that it was sexual rather that it was in an inappropriate context or evidencing harm.
I find a lot issues around censorship are not satisfactorily resolved by asking whether material should be allowed to be published but how and in what circumstances it should be accessed and by whom.