Given that it's such a niche scene, I think its also very likely that someone passing off another person's design as their own would be identified fairly quickly.
When I talk about opportunities - I'm really talking about individuals wanting to develop their own Irish layouts or use examples like @Rob R's MGWR wagon to learn CAD. I love reverse engineering things and understanding how they work, or why the designer made the choices they did. So my plan is to have a play with your design, use it to understand and learn from your approach to designing a wagon, then have a go at my own models.