Hi Mark,
Thanks for the kind feedback.
The core idea is a Spline (Path) with another Spline (Profile). Then a Sweep is used.
The Profile Spline would extend the shape as it runs with its middle along the Path, so I used the Transform Element Capsule to get the axis to the "outer" point. Half of the width of the profile. In this way, the Path is also the final size. One of my targets here was to define the size without guessing.
With an Extrude, the Path creates the Fill of the door. I used a Bevel here, so it doesn't show up on the side (nearly no offset)
The XPresso handles the "half profile/axis" process and the User Data Mixer. Most of the parts (Formula) are done to allow the profile to shrink when the door is much smaller than the frame. This is more for comfort than needed.
My best wishes