Hi there, I'm having a problem related with assigning specified flow boundary conditions to my UGrid / Modflow-USG model. The error appears when I do the '' Map to MODFLOW'' option while converting my conceptual model to UGrid numerical model. I have read the helping document  saying that If you want to use ''Specified flow boundary condition'' the UGrid must be a stacked grid. A stacked grid is one in which there is no vertical discritization of layers and the horizontal discritization of