I actually wasn't getting any critical problems like lockups, so I don't know what was going on there, but in my tests the bombers escorting the avenger would randomly "lose it" when it went through a wormhole, despite the code explicitly trying to get them to go to it if it was off planet, etc. Lots of mysterious behavior, and a few hours of debugging didn't really reveal the culprits.
And with it causing lockups in some cases for some people but not others... the big problem would be knowing when I was "done", in the sense of it working properly, which is a bit of a concern for reaching official-level stability.