I often create models with multiple support conditions. Because of STAAD's requirements on support degrees of freedom I have to model lift cases first. This means that I cannot model seismic cases first as required if I want to use STAAD's seismic load generator. Consequently, I have to do my own loads for seismic. I don't understand why STAAD can't do this in any order if I, a mere human, can. This is a major inconvenience. I don't know what's going on under the hood that requires this restraint but it seems to me it should be fixable. Please allow seismic generated loads to be entered in any order.
The current requirement is determined by the size of the stiffness matrix which is defined by the first analysis set. However, I would certainly agree it is a frustration and we do have this in our backlog to address.