Been down all those roads and then some.
Nothing seems to work.
And the senior Apple advisor I spent 1.5 hours with on the telephone this morning couldn't come up with anything either (except take me through some fantastic voyages, setting up root access accounts and stuff which quite frankly scares the hell out me — and I can't figure out how to get rid of the Other account set up in some invisible fashion).
This should be a trivial problem, but it sure isn't.