I have had a problem with the org mode calendar export with emacs. It looks like org mode uses some uid generation exe which generates non unique UIDs. I am not sure why this is to. Even when I
set the UID format to include the date format. Because of this, the ics file import into google calendar or a thunderbird import fails to import all tasks that were reported as Scheduled in the org mode document.
Anyone with similar experiences.? I put this up on stack overflow but there was no response.