General Tips
You can export your project as a 3D HTML simulation in one single file. Compressing an HTML file will remarkably reduce its size and you can send it by email.
The following links are examples of 3D HTML simulations:
● https://robodk.com/simulations/UR-Paint.html
● https://robodk.com/simulations/Welding-3-Fanuc-Robots.html