So I've been working on a small island mod and created a new world space. I wanted to test the mod to see what the island looked like in-game, so I created a cell with a house interior added a door that connected to a door in TestingHall and connected another door to the exterior world. I even added a tombstone in front of the right door in testinghall so I would know which one it was. However, when I did coc TestingHall the tombstone and door weren't there. I tried coc AAThatchInnDummyCell (the name of my interior) and that was also a no go. So it seems that nothing that I do in the mod is affecting the actual gameplay. And the mod is activated in data files. I've tried a new game, and unistall/reinstall Oblivion, and restarted the computer, nothing seems to work. So some help would be very appreciated as I would not like all my hard work on the island be wasted if I had to start all over.
Thanks.

Are you using http://cs.elderscrolls.com/constwiki/index.php/Windows_Vista

XP actually

Make sure you have your game properly patched to v1.2.0416, especially when you reinstalled and such.
Plugins created with the 1.2 CS (nowadays all) will just "silently" be ignored by a pre-1.2 game. It won't complain or give error messages or anything. It just won't use any of the stuff in the plugin.