> Well, I can't delete it, because that causes a crash, and I can't
> seperate because that crashses as well.

After you open it, immediately save it out again as a new file, like starship2.3dm. Now open starship2.3dm and you should be in better shape at that point. But there will be some duplicated surfaces that you will want to remove.

I think that trying to join 2 pieces that have coplanar faces may be the cause of this.

- Michael