Except those few occasions when Darka was attacking CE i got whined that while i try to negotiate my armies are attacking and negotiations pretty much ended there 
If you are looking for peace you don't attack, if you are looking for surrender you do. The point being Darka has no advantage and thus was just angering CE during peace talks. CE is looking for surrender, they get peace regardless its what they get from the surrender that is being determined.
Just because its during surrender talks doesn't make it ok, so you can still bitch about it in ruler's channel if you want, but I don't know how much that will help.
At Noldorin,
I am calling complete BS on the ice being the reason that Darka lost. The ice sped up Darka's loss, but it didn't cause it. Darka was losing that war and it was not improving for Darka. Darka stole some of Lyonesse's regions, good for Darka, they were still losing that war.
