zmacs split screen; c-x o loses

[David Chapman <zvona@MIT-OZ>]

In zwei in Release 4.1, System 222.186, Hardcopy 11.14, Zmail 74.43,
LMFS 30.26, site configuration 19, on Lisp Machine Two:

This is about the split screen item in the zmacs menu.  

* with three windows, if you do c-3 c-x o, you end up with one window.
c-2 c-x o doesn't.  I thought that a numeric argument of n was supposed
to move you to the nth window.

* if you ask for three windows, the bottom border interacts weirdly with
the bottom of the zwei frame to produce a double line.