CD's right there - see what happens if you make details 1, 2 and 3 children of detail 0.
If that doesn't help, next try removing the insignias to see if they might be intefering with the LODs in any way during PCS' autogen.
Yes I tried triangulating and yes I know how to make debris.
Never doubted it - but in this case you used debris that you did not
make, the geometry of which you may, therefore, not be totally familier with - meaning whether or not you know how to make debris is irrellevant.
Besides, I've never seen any of your models with full hull mass debris, which was why I pointed it out in the first place, since it's just a cool thing to do.
Also, I was pointing out the final triangulation not because I didn't think you knew about it, but simply because I've had one or two models that wouldn't convert at all until I made a final triangulation. Even though the total polycount did not change, the models converted fine afterwards. Still haven't figured out why.
Another thing that somehow
occasionally helps otherwise inexplicable crashes is to completely collapse your hierarchy down to detail0, select a light or something else in the scene, re-select detail0, and then save as a .SCN - give that a go too.