I went to delete a ship design that I'd made in a previous game. So I went to the Shipyard screen and clicked on Delete. Then I realized that I'd tried to delete the colony ship design, so I clicked on my custom design and then on Delete. Nothing happened. So I clicked on Delete again. Nothing. Then I clicked on Obsolete, which at least made the design disappear from the list. Then I clicked Done.
Leaving that screen, I got a GNN report announcing the completion of a colony ship that had finished building that turn. When I dismissed that, *then* I got a confirmation box for the ship design deletion. So I accepted it, and got *another* confirmation box, which I also accepted. Immediately after that, GC2 crashed.