I had the same problem -- not showing up in the calendar, but in the list. Before I had a chance to really pour over it and see what I missed, omegatron posted the attachment above, I used that to check what I'd missed, and there was a whole section I missed in addevent I believe. I really wish I could tell you what it was, but I don't think I have a copy of what I had before I fixed it. I'll look though, I have Beyond Compare set to automatically backup things I change. Heaven knows I don't ever remember.
I have a working version here:
http://www.fishingfordeals.com/forums2/postlist.php?Cat=&Board=calendar if anyone wants to try it. It's just an empty testboard, and you should be able to post anonymously.