I haven't touched this in a while, perhaps I shall modify it soon, but to clarify:
Everything is set on triggers that are based on how the battle progresses, not on timers. Also, this is intended to be for player vs. player.

I waited for Isengard to attack... They did not attacked... No timer for rohirrim, no timer for Isengard attack. Nohing is set. Or I am missin sth?

so one person saying that isengard is OP and the other saying that helm's deep is op....lol

But valid concerns.

*Recovering Civ Junkie: the rohirrim show up when the attackers get through to the second gate (as they should). Attackers should not be able to build market, I will have to fix that.

our game was clocked at 4 hr 30 min, no rohirans showed up, nothing came from the forest. dont know what was supposed to happen. the attacker had the upperhand with all the access to unlimited resources and being able to make a market. could make seig that made it unfare.

how do i begin to play this? Where do i find it? in the Custom Senerio?

true. That is part of the motivation to logging in Fangorn, you take time to build up more seige weapons. But I shall add a few more to start off so you can keep the pressure on at the beginning.

Just played it, Helms deep was awesome, but the offensive army was not adequate and got slaughtered. They need trebuchets and siege weapons and alot of stuff.