The "disintegration" was interesting. I wonder if there was air trapped anywhere in the system, connected to the outside by some slow leak, that would build up pressure over a long time but not be able to vent as you brought it up.

That "gumdrop" configuration of the re-entry capsule is one I've used a number of times in spacecraft designs. It's a very stable shape for reentry, although as a ballistic reentry vehicle, the g-loads are pretty bad for people. Most designs I've used it in involve engine capsules for recovering complex (and expensive) rocket engines from near-orbit velocities.