Treelor

How does TargetDestroyed determine if a target is actually destroyed? I'm running 5dim's (and making my own) pack and I've certainly put many targets out of commission but they're never really counted as destroyed. Is there perhaps a way I can define a custom parameter, instead? Maybe some way I can check to see if the craft has less than 40% of its parts attached or something?

Are Mavericks/Hellfires supposed to lead ground targets? It doesn't look like they do, which leads to a lot of misses for anything that isn't stationary.