I have a quite similar problem even though my bars are still
'upright'. I coulnd't yet figure out how to name EACH column and if
this would work how to write the columnnames vertically. I'm
actually using CF8.
Sorry no big help :-)
change isHideOverlapped="true" to "false" and ALL your labels
you can change lots of other styles there, too.
if you do not want to change the default.xml - save it under
website root with whichever name you want to give it (but
extension), make changes in that file, and then reference it
STYLE attribute of CFCHART tag, i.e.: <cfchart