= Small-limit preservation is insufficient for the large elements-colimit criterion
Let $\mathcal C$ be the ordered <category> of all <ordinals> with an added greatest object $\infty$. The <categorical presheaf> with $X(\alpha)=\{*\}$ at ordinals and $X(\infty)=\varnothing$ preserves every small <categorical limit>: a small supremum is an ordinal unless its diagram contains $\infty$. Its <category of elements> consists of all ordinals, and their projection has the large <colimit> $\infty$. Nevertheless $X$ is not <representable>: an ordinal representer has bounded support, while the representer $\infty$ has a nonempty value at $\infty$. Thus preservation must include the possibly large opposite elements diagram. The dual functor $X^{\mathrm{op}}:\mathcal C\to\mathbf{Set}^{\mathrm{op}}$ also disproves the comma-projection criterion for a right adjoint under small-colimit preservation alone.
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