I'm running static load studies on a bent sheet metal structure, which is held together by pin connectors. I have a gravity load applied, and would like to apply a distributed mass to one face of the structure. When I try to apply a distributed mass (or a remote load for that matter), SW throws an error message that states "unable to read write-only property". How can I resolve or work around this error? The photo below shows the structure (symmetry fixture used), study run without the needed mass represented.