Open Roads SS3 > Create Terrain Model By Graphical Filter > Problem with triangulation of cells representing spot elevations

Random Terrain Points (spot elevations) in our mapping DGN file are represented with a cell that looks like a white plus symbol as shown in the second screen capture below. I have created terrain filters and a filter group which I use with the command ‘Create Terrain Model by Graphical Filter’. The problem I’m having is that each vertex of the plus symbol is being included in the triangulation rather than only triangulating the origin of the cell. See the third and fourth screen caputures below. Is there a setting that will triangulate only the origin of the cell?