The cloud could only exist in its unique conformation if all the physical, chemical and electrical factors were operating within very tight limits.

No. Different conditions make different clouds.
The only physical constant involved in cloud formation is the triple point of water, and it is not critical.

The physical constants that govern the universe have to be exactly as they are or chemistry could never happen.

Had it been a one-off event (I'm severely sceptical myself),

Dr. Nick Lane is not sceptical.
He is convinced.
I am not qualified to judge, but I doubt your credentials compare with his.
http://www.nick-lane.net/About%20Nick%20Lane.html

And, I have not mentioned God.
Just things that amaze me.