difference problems

In the excellent “classroom tutorial book” is a house made from two cubes, one inner, and one outer. that worked.
But when i put a cube in as a window, REGARLESS of which i select first and click W.It does not work, in fact it creates a duplicate.
It does not creat a hole.
I know how it is SUPPOSED to work. Does anyone know how to make it work in 2.34?
Thanks, Jim
“• The Difference operation is the only one in which the order of selection is important.
The active object (light purple in wireframe view) is subtracted from the
selected object. That is, the resulting object surface encloses a volume which is the volume belonging to the selected and inactive object, but not to the selected and active one.”

Say you start out with the following:
~[cube one]
~[cube two]

you select [cube one] first followed by [cube two].

if you use difference, you end up with the following:
~cube one
~cube two
~difference of one and two

you probably want to get rid of cube one and two (or move them to another layer) and render again…

i dunno if this helps…