Yes, it’s true we overlooked the sorting aspect when creating the .zip file to distribute for users to add to the Custom workouts. Zwift game logically sorts the workouts based on their content, it doesn’t look to the folder than are stored in the disk. This should be improved.
In the meantime the work-around to know their correct order is to look at the workout file contents and search for < subcategory > (Week 1, Week 2, etc.) and < subcategoryIndex > (the sorting within the Week)