Unfortunately there is much confusion about what is allowed or prohibited in terms of promotion, or dealing with commercial products in the XSim forum.
Though some sections provide a vague description...
DIY motion simulator projects
Community DIY motion simulator projects with X-Sim. Share your projects with reproduction hints and learn from others. Commercial projects are not welcome in this section.
...I agree that there is a need for some more specific guidelines.
But I have no expertise regarding this issue and my english isn't good enough to write legal stuff either. So probably it would be best, if someone could work something out with the XSim chef (Sirnoname), to bring some light to the issue.
Because there is much confusion out there, and I am tired of second guessing of what should be allowed and what not as well...