I have had similar problems with crashes when trying to delete large objects (usually treelab trees)from the create menu. Generally happens when I try to delete more then one object in a session. One cure is to delete one object, shut Bryce down, restart it, delete the next object, shut Bryce down, restart it, etc. etc. Tiresome but prevents crashes. Bryce seems to be doing a lot of work during deletes, so I would guess it is shunting stuff around in the memory, and possibly doesn't keep track correctly of where it is putting things, hence the crashes, which leave the .TMP files lying around.