It's interesting that apparently so many people have had issues with dForce as I haven't had similar problems. Yeh some things may explode at random but generally it works for me most of the time and usually simulates quite quickly even in heavy scenes.
There are so many variables at play with GPUs, DS versions, scene set-ups and drivers I wouldn't even suggest what might be issue. A random "butterfly effect" issue where insignificant differences can lead to different outcomes.