It works for me on the full  (non-miniroot) partition on my
3MAX.   ps is not working because it isn't finding a kvm
database, or it's finding a corrupt one.

>Anyone want to suggest where to look first?

Do you have  a tmp (or /var/tmp) directory? How about local timezones?

Try running it interactively in single-user mode and see if
it complains more meaningfully.

I'd put together a clean, full root distribution, only I just replaced
part of my kernel tree from NetBSD-current, which doesn't build.
So it goes.