Exports to ics ends up in an empty ics-file like this:

BEGIN:VCALENDAR
VERSION:2.0
X-WR-CALNAME:OrgMode
PRODID:-//Johann Spies//Emacs with Org mode//EN
X-WR-TIMEZONE:SAST
X-WR-CALDESC:
CALSCALE:GREGORIAN
END:VCALENDAR

The html file is good.

ps and pdf exports fail totally with no output at all. When trying to use ics, ps and pdf exports I get

Wrong type argument, stringp , nil

I have the following in my .emacs

   (setq org-agenda-exporter-settings
                '((ps-number-of-columns 2)
                  (ps-landscape-mode t)
                  (org-agenda-add-entry-text-maxlines 5)
                  (htmlize-output-type 'css)))

I am using orgmode 8.2.1-1 on Debian with emacs24.

What am I missing?

Regards
Johann