Triggering samples with Addictive Drums

Hi. You could use TTS, which is very light weight, or SI drums. Session Drummer 3 is also a good included drum Vsti. You might have to relocate some of the hits, as they will likely not be the same from AD2 to the others.
All the best.

Session Drummer3 can be extended by 3rd party kits, you can mix and match pieces from different kits. It also supports multitrack routing. Romplers like this don't usually take much CPU power, yet require much RAM. But you can freeze individual tracks and process them to your liking with plugins. That'll save you some computing power.  AD2 has great buit-in FX and supports disk streaming, whereas SD3 and SI-drums don't.
 

Session drummer will play almost anything. I sampled my drum kit and often use it to trigger sound effects. 
The quality of most of the drum sounds in TTs-1 are possibly the lowest used in Sonar, SI drums as well. I could never go back to using those. I don't mind the TTS_1 kick and some percussion stuff but the snare and hi hat drive me nuts. 
Addictive drums does not put any heavy load on my computer. And you can always bouce or freeze the tracks if your having CPU issues.  

+1 also for Session Drummer 3. VSTis like AD2 which have internal processing are a double-edged sword. Upside is they have internal cross-talk to give the effect of mic bleed (or warp a drum into almost any other sound), but at the downside of processing power.
 
I forget now if AD2 maps to general MIDI (GM) format if pulling MIDI from its UI, but it is close (it actually uses more notes, so some may not sound unless dragged to the GM region). IIRC, they have notes "out of bounds" both high and low that SD3 would not fire unless you move them.
 
Also, if you get cramped into a CPU corner, do not forget you have the ability to either freeze a synth, or bounce it to new track(s) and then archive the original. Even CPU-aggressive VSTis can be "tamed" in this manner, so that method may actually be an alternative for working with AD2.