If you have a world, devoid of any obvious geometry, with player capacity 4, but the capacity meter for physics/objects/geo says ~15%, how do you find and delete whatever secret stuff is chewing up such a huge percentage of build capacity? Sweep selecting everywhere above/below/around the grid out to a good distance finds nothing. I suspect either small locked objects or very very distant objects? Unclear where it came from, but I believe the import history of the worlds leading up to this one includes the Launchers and/or Throwing Examples from Meta, which were known at one point to be space junky.
Needless to say, I can't just "start over" with a new world, as there is a lot of work already put into this one. Need a way to delete the junk.