I have been trying to put a shack in the hills of Balmora.
I don't want to stay at Caius place because he wears no shirt and doesn't assist me when the Dark Brotherhood attacks.
I have placed the exterior and interior of the shack and also the doors. Unfortunately the exterior door always rotates open as an animation, instead of teleporting me to the interior. I used COC MyCottageInt and tried the interior door and it teleports me outside just fine. I checked the "info"(shows how it is used in other cells) on the exterior door and it appears to be a portal door and I clicked the portal check box and set it to the interior cell.

Yet the exterior door continues just to swivel open instead of teleporting me. What is happening here? It seems to defy logic, but perhaps I'm missing something.

I am using in_redoran hut door and ex_redoran hut door. even tried making them both interior doors and that didn't work.

I noticed that with another save the door worked correctly.

If you are building a mod, it's always best to test your work with a Save file that has not interacted with your mod before.
Otherwise, references are already made with your objects and any changes you make afterwords can be ignored by the game.

Updating your Save file with Wrye Mash after each session in the CS will also avoid these types of problems.