In Links, a hole path and boundary is created by the designer to help with the computer AI, and also with statistics like fairways hit. I have seen no sign of these on the Course Forge hole creation video, so am presuming that they are not used with Course Forge.
Are the shapes created, assigned to holes instead? If so, I hope that they can be assigned to multiple holes, otherwise I can see no way to create courses that have crossed or shared fairways on them, and still have the correct statistics recorded.