Hi Sye,
I have taken another look at the model you suggested and had a few queries as it relates to the Reference Load Definition (mass type reference load in this case).
1. Which section in the technical manual speaks directly to this type of reference?
2. I noticed that you multiplied the self-weight Y by a factor of 1 instead of -1, is there a specific reason why you did this?
3. Why did you reference the gravity loads in the direction of X and Z, seeing as though these loads are acting in the Y direction only?
Questions number 2 and 3 are in direct reference to the referenced file you presented.