Here are a couple more pics of that bird. Do these give any more clues to its sex?
They are some really great photos. Helps to see it up close. Yeah I think that's a Roo personally and he's only just got his full feathering in (the tiny yellow down feathering that still exists on his head is still slightly present) so im thinking he's between 6 and 8 weeks old. It's the redness of the comb and the undefined tail feathers that tell me that's a boy. I could be wrong of course, but if it were my birds, I'd label it as a Rooster.