Step 1: Custom Door Creation
Create a door using slabs, beams, walls or other objects. Make sure that the top of the door is oriented toward the project north, as this will determine how the object is positioned within the wall.
Step 2: Creating the Wall Opening
In order for the wall hole to follow the contour of your door you will need to place a slab that encompasses your object and outlines its boundaries. Once the slab is created open up its Slab Selection Settings dialogue box and enter WALLHOLE in the ID parameter under the Listing and Labeling tab. This will enable the slab to puncture the wall and remain hidden when the door or window is placed.
The thickness of the wall opening slab and its placement relative to the door or window elements will have a bearing on the positioning of the door within the wall.
Step 3: Saving Your Custom Door
Select the elements that make up your door, including the wall hole slab, and view those objects in 3d Axonometry. Open the 3D Projection Settings dialogue box found under 3D View Mode in the View menu. Adjust the Parallel Projection Settings so that you are viewing the Top of the objects.
Now select Save Object as… found under Libraries and Objects in the File menu. In the dialogue box that appears, select Door for type. Click on Options and make sure that Editable GDL Script is checked. This ensures that the wall cut follows the contour of your wall hole slab that you have created.
Finally, name the door, pick a location to save it and click Save. You should now be able to place your door in the project.