Daniel:
For a quick and dirty solution, you could stack two short doors vertically, this will give you individual control over the 3D opening angle of each panel. The shorter height may play havoc with the door panel styles and trim, it depends on what you are trying to achieve.
If you make your own door, you will need to create a new parameter for the 3D opening angle of the second panel, and this will need a variable name that is different from the variable name of the first panel. You will also want to add another parameter to control the height of one of the panels. The rest of the script should be very similar to a single swing door part.
HTH
David
