Welcome to My Monday Morning Blues:
Ouch
What exactly were you doing to occasion these series of crashes this morning you ask?
Welp, I was cutting and pasting a small number of 2D/3D symbols and attempting to paste them elsewhere, appx -100' from current location. Internal origin is 0,0.
Edit: Ok, so: the items to be moved were on a couple different labels. I put em all on same label, no cut/paste, just Shift+Moved to new locale on layer. So far so good. Cmd+Save & immediate Crash Monster Redux.
& even deeper than the ouch is the lack of productivity