Before we go too far into Setterfield's ideas, I think it is important to establish whether or not observations are consistent with constant physical forces. Mind you, I am not saying that the observations "prove" unchanging physical constants. Rather, I am asking foreveryoung (or any other creationist) if our observations would be different if constants were in fact constant over the last 13+ billion years.
The problem that I see with the creationist argument is that it boils down to the claim that evidence for changing constants is indistinguishable from a universe with unchanging constants. Specific to this thread, should uranium haloes appear differently today if the laws in the past were the same as today?