A machine designed by a human to be useful to humans would signify intelligent design because it fulfilled an intended purpose – to benefit its designer. If a machine had only the ability to maintain itself and reproduce, would that be useful?
It might be useful to the machine but not to an outside intelligence, so no intelligence need have been involved in the design.

The purpose of living beings appears to be to maintain themselves and reproduce. The ability of humans to add complications to their lives, such as trying to understand their world, making complex entertainments or creating obstacles to overcome, does not change the purpose. This suggests that there was no higher intelligence involved in their creation.

But let’s turn that supposition on its head: It’s evident to the relaity-based community that cell biology comprises a set of complex systems which has evolved without inelligent design. It’s also evident that at the macroscale humans perform intelligent design and fabrication of complex systems. But what’s not evident is whether intelligent design and fabrication of complex systems is possible at the nanoscale.

Indeed, the evidence to date is that intelligent design of complex systems at the nanoscale is very, very difficult, and that it may be impossible.

So the question for the creationists is this: If it becomes evident that the intelligent design and fabrication of complex nanoscale systems is impossible, doesn’t that imply that the ab-initio intelligent design and fabrication of biological systms is also impossible, and so doesn;t that argue for the non-existence of an intelligent designer of biological systems?

It all comes down to ego and a subconscious fear of death.

Thanks for the tip, Guthrie. I’ll write a comment on this slightly alarming development later.