I have a sheet metal part on which I'm trying to simulate a remote load. There are some screw hole locations though which the load passes, however, when I select these faces I get the error message that "face along thickness of sheet metal invalid selection". First of all, what does this mean. Second of all, this same simulation is working on another similarly constructed sheet metal part (I'm comparing two design options). Lastly, how can I apply the load to these holes and not get this error?