I didn't forget anything and this is more like a complicated enhancement than a bug. [;)]

Here's an other workaround easier that db4tech's one:
- Add first a Door frame at the place you want while magnetism is active.
- Then add the Open door at the same place with disabled magnetism (press down the shift key to disable temporarily magnetism), using Furniture > Align menu items and arrow keys to help you place it correctly.
- Finally if needed, group the two items to avoid future auto resize.

See the joined example.