Hi Jonathan,
The group you created (Curve Rotation) is not working. If the 2 nodes "Align Euler to Vector" are set to auto, the supports come back fine, otherwise not. Below is my file:
Ah, good catch! My thinking was probably that setting a pivot axis makes the rotation more stable, since that helped us several times previously, but with both the normal and tangent to control it, that shouldn't be a concern. Pretty sure I was just overthinking it in the lesson and you can go ahead and leave them on Auto.