Do you have kids? Have you ever let your kid do something dumb, knowing what the outcome would be, just because you know that's the only way he/she would learn. Or even better, warned your kid not to do something, but not tried to stop him, because you know that no matter what you say he/she is going to do it anyway?
The above statements you made are contradictory. Creating the universe, and specifically humans, and giving them free will is not intent, it is ability. The two are not mutually exclusive. Just as in the example I presented above, the child has the choice not to do something that will cause it harm, even though it has been warned not to do said thing. Do you blame the child or the parent for committing the action.
Umm, that's a pretty ignorant statement if I do say so myself. Generalizing an opinion about another person concerning multiple fields of science, based on one statement concerning one theory does not a good argument make.
And to the original statement, it is actually physically impossible for one pair of "humans" to have existed first. There had to have been an exact moment when the first male and female humans were birthed. Now whether are not these were the only two humans that gave birth to other humans is debatable, but considering how evolution works, I would find it highly plausible that these "humans" passed on traits to other species that they were compatible to breed with, but not neccesarily the same as we would classify them today. Then you have the question of what was qualified as "human" concerning Adam and Eve?
According to anthropological evidence we all came from a small area in Ethiopia so there couldn't have been a very large population of the first humans anyway.