Well, for starters, the Anthony Flew story turns my stomach, so they lose credibility out of the gate for trying to appeal to the "once I was a staunch atheist, now I believe" bullshit.
Other than that, it's a hodge-podge of wishful thinking and hopes that the credulous will simply accept that they must be right because of the first cause argument. As usual, it is beyond them to have to explain the existence of a creator, so they simply insist there had to be one, just because there is currently no explanation for the known universe.
they fail to understand what it means to truly explain something, and they are as unwilling as most apologists to admit there is something they simply do not know. They simply assert, with zero explanation, facts, or evidence, that there must be a creator.
In short, they have nothing.