Mostly, except that instead of copying all of conf.php there, you'd want to copy the appropriate fragment from /etc/e-smith/templates/home/httpd/html/horde/imp/config/conf.php. I don't know which one that is; I don't have a 5.5 installation here. If you go to that directory and do 'grep change_folders *', you should find it pretty quickly, though.
Oh, and I prefer pico, but that doesn't make much difference.
You could do console-save, but it's really overkill. Try expand-template instead:
# /sbin/e-smith/expand-template /home/httpd/html/horde/imp/config/conf.php