What a tremendous thread, a classic for the " best of section " I would say.
This is a bit off topic, but I am surprised Tammy says she hasn't heard the argument about apparent design proving a Creator, didn't Paul start it all with "Every house has a builder...."?
I agree with Talesin too, that when discussing this with JW's or others who do not understand how Science uses the word "Theory", very different from our everyday usage, we need to express ourselves well.
Perhaps referring to "the proven evolutionary process" or something similar but less ponderous, then the onus is on them to prove that evolution does not, and did not happen.
I am confident that one day it will be proved to us how life got started here on Earth, we already have the hypothesis in place.
The argument about a designer will still probably rage on though, many humans are frightened by the concept of individual responsibility it seems to me, so they like to have a God to blame for the problems of society, and to leave it to "god" to sort those problems out.