quote from D2.0
Likewise, because a chemical process "behaves" like an engine, does not make it one. It's just a chemical process.
You are not paying attention. Molecular machines are not chemical processes they are literal machines! One more time:
With parts that resemble pistons and a drive shaft, the enzyme F1-ATPase looks suspiciously like a tiny engine. Indeed, a new study demonstrates that's exactly what it is."
Science News vol 151, p173
This peer-reviewed article is saying that the F1-ATPase enzyme IS a tiny engine. It isn't saying that it is a chemical process that "behaves" like an engine. Chemical processes don't "behave" like engines. Since when do chemical processes have parts that resemble pistons and a drive shaft?
Quote from D2.0
Why is it not an engine? Because the concept of an engine was not derived from observing some natural chemical process and then mimicing it.
Right. Scientists would never have conceived of an engine from observing chemical processes but scientists are mimicing the nanotechnology found in biology to design nano-scale machines. That's possible because the molecular machines in nature are actual machines and not chemical processes.
Quote from D2.0
So I reiterate: Do you have any objective criteria for determining what would constitute evidence of design and by necessity, what wouldn't?
One more time. Design is the prima facie interpretation when confronted with a machine. You have provided no good reasons why one should not consider molecular machines to be literal machines.