I am converting my forum to Beta 2 right now, but when it is up again I have just such a hack in testing (well I have lent a thread to Leesester who is making it) and it will allow you to use a wider range of doors as apartment doors). The only other way to do it would have been to edit the LUAs.
This will be awesome, Inge. I could use some different doors in my themed neighborhoods. So you're going to do what I saw you post on MTS2, and have the doors themselves have the option to change the model?