For me, my ship always becomes top-heavy in the atmosphere with all of the foldout solar panels and science modules. The ship does a flip and I NEVER activate the parachute in time. Also, when I accidentally downloaded 1.0 for the first time wrong, the physics caused any ship at more than 10% throttle to tear it apart. It turns out I had 0.25, 0.90, and 1.0 together, causing all of the physics to ruin the game. I fixed it.