Hi,
I have to say that I avoid using ARA2 in Nuendo the way it “should” be used, as I had some unpleasant lessons learned with it.
One of it is this one:
ARA2 Bug, clip gain calculated twice when using crossfade
Also using it on large source Clips may lead into trouble.
So at the moment I always use “bounce selection” before and after I use ARA2, which makes the ARA point kind of pointless.
I do not want to bash Nuendo or sound discouraging… 
But after 3 days without replies I thought I’d share my dealing with ARA2.
Cheers,
Dirx