Is that a shell element model? You need an element that has rotational degrees of freedom.
I think there is a trick that you can do with a point, but it may require free body forces. is that what you are referencing?
I'm a bit late in a response, but I found this post because I had the same question. I'm still not certain how to get a reaction moment with a solid mesh in a nonlinear study.
I can, however, solve the issue for the original poster. You can indeed fix the orientation of a beam joint. The option is rather hidden: to reveal the "Advanced Fixture" - "Reference Geometry" option you must also have a solid body in the study at the same time as the beam mesh body. So in the model slap in an extruded box to create this extra body. Then go back and right click on "fixtures" and add this "advanced fixture". Notice how you can specify a joint, exactly as you want to do. Once you're all setup go "exclude from analysis" the bonus body.
This must be some sort of bug in the logic SW applies to which menu options are available.