I have some code structure very similar to this example: https://gist.github.com/ibarovic/3092910
Everything is working pretty well, except that the delete checkbox after each Book element is not shown at all. If I change
{% crispy formset formset.form.helper %}
to
{% crispy formset %}
the delete checkboxes are shown, but the form does not work anymore (b/c the HTML form tags are used not only once).
I suspect that those checkboxes are not known to the BookForm (b/c they somehow get added later by the inlineformset_factory), so they do not get added to the layout and are ignored. I have no idea how to circumvent that though.
I found a solution thanks to this: Django crispy-forms, BaseGenericInlineFormSet & allow_delete
In the BookForm (which gets repeated many times) init, you can add something like:
self.helper = FormHelper(form=self) # or manual layout
self.helper.form_tag = False
i = self.helper.layout.fields.index('title')
self.helper.layout.insert(i+1, layout.Field("DELETE"))
The capital letters "DELETE" field then gets added to each single BookForm...