Doc, I want to support you. I also have the feeling this is a bug. But AFAIK this has always been described in the kix2010.doc
 Originally Posted By: kix2010.doc

COPY
Action
Copies one or more files or directories.

Syntax
COPY "source" "destination" [/h] [/s]

If the source or destination specifies a directory, please make sure to add a trailing backslash.

IMHO newer versions of KIX should not break scripts, if possible.