Taking the Gateway

[deltafan]

OK, I'm doing a custom battle on the Rome map, I've got two seige towers and I get my men off the walls on to the floor in front of the gate. So as the first of the men come down, I tell them to attack and they do nothing. I have to click it many times to get them to even move. How do I get them to be more responsive? Second problem is I click the floor on the inside of the gate, just behind it, and it never says gateway taken, the guys still on the outside don't go near the gate, and the guys on the inside go close to the gate and it doesn't open. How do I take the gate?

Any help, thanks.