"SewerGEMS stopped working" when selecting element

Question

Has anyone else experienced issues with the "SewerGEMS stopped working" dialog appearing all the time in the new 10.00.00.40 version? 
 I installed the new version and am trying to work with an old model I did in the previous version. But whenever I click an element in the model it pops open the error message. If I create a new model and draw a few elements in it it doesn't seem to have the same problem, though. 
 Is there something I'm missing here? Any idea what might be causing this bug? 
 Appreciate any help you can give. 
 Thanks! 
 David 
 
 Here's the error message, by the way: 
 09/23/2016 11:25:33.45 System.NotSupportedException: Specified method is not supported. 
 at Haestad.CivilStorm.Calculations.SWMM5.Domain.SwmmNetworkMapReaderWriter.CheckHeader(BinaryReader br) at Haestad.CivilStorm.Calculations.SWMM5.Domain.SwmmNetworkMapReaderWriter.ReadMapFile(String mapFileName, IDictionary& nodeMap, IDictionary& linkMap, IDictionary& catchmentMap, IDictionary& elementCodes) at Haestad.CivilStorm.Calculations.SWMM5.Domain.SWMMResultDataConnection.LoadMapFile(Int32 scenarioId) at Haestad.CivilStorm.Calculations.SWMM5.Domain.SWMMResultDataConnection.IsMappedLink(Int32 elementId, Int32 scenarioID) at Haestad.CivilStorm.Calculations.SWMM5.Domain.SWMMBasicFlowResultsRecordDataBroker.GetValuesOverTime(Int32 elementID, Int32 scenarioID, String fieldTypeName) at Haestad.Domain.ModelingObjects.ResultTimeVariantUnitizedFieldBase.GetValuesOverTimeImpl(Int32 elementID, Int32 scenarioID) at Haestad.StormSewerProduct.Adapting.Graphing.StormSewerProductResultGraphFieldDefinition.GetValuesImpl(IGraphSeriesModel graphSeriesModel) at Haestad.Framework.Adapting.UnitizedGraphFieldDefinitionBase.GetValues(IGraphSeriesModel graphSeriesModel) at Haestad.StormSewerProduct.EditorModel.Graphing.StormSewerProductGraphSeriesModel.GetGraphSeriesValues(IGraphFieldDefinition fdX, IGraphFieldDefinition fdY, Double[]& xValues, Double[]& yValues) at Haestad.Framework.Windows.Forms.Steema.Components.LineChartControl.BindSeries(Series ais, IGraphSeriesModel aigsm) at Haestad.Framework.Windows.Forms.Steema.Components.LineChartControl.InitializeChartSeries() at Haestad.Framework.Windows.Forms.Steema.Components.ChartControl.InitializeChart() at Haestad.Framework.Windows.Forms.Steema.Components.ChartControl.Refresh(Boolean bottomAxisShown) at Haestad.Drawing.Windows.Forms.Components.QuickGraphViewerControl.RefreshChartControl() at Haestad.Drawing.Windows.Forms.Components.QuickGraphViewerControl.NewItemSelectedHandlingMethod(Object sender, NewItemSelectedEventArgs e) at Haestad.Framework.Application.QuickGraphViewerControlModelBase.OnNewItemSelected(Object sender, NewItemSelectedEventArgs args) at Haestad.Framework.Support.DomainSelectionChangedHandler.Invoke(Object sender, DomainSelectionChangedEventArgs e) at Haestad.Framework.Support.DomainSelectionEventChannel.OnSelectionChanged(SelectionSetItemCollection selectionSetItems) at Haestad.Drawing.Domain.LayoutControllerBase.HandleSelectionTool_MapSelectionChanged(Object sender, MapSelectionChangedEventArgs e) at Haestad.Drawing.Tools.SelectionTool.OnMapSelectionChanged(IList selection) at Haestad.Drawing.Tools.SelectionTool.Handle_InteractionCancelled(Object sender, DrawingInteractionEventArgs e) at Haestad.Drawing.DrawingInteractionBase.OnInteractionCancelled(IDrawingControl drawingControl, Object geometry) at Haestad.Drawing.DrawingInteractionBase.HandleInteractionCancelled(IDrawingControl drawingControl) at Haestad.Drawing.DrawingObjectSelectionInteraction.HandleMouseUp(IDrawingControl drawingControl, MouseEventArgs e, Keys modifierKeys) at Haestad.Drawing.Windows.Forms.Components.GLDrawingControl.GLDrawingControl_MouseUp(Object sender, MouseEventArgs e) at System.Windows.Forms.Control.OnMouseUp(MouseEventArgs e) at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks) at System.Windows.Forms.Control.WndProc(Message& m) at Haestad.Drawing.Windows.Forms.Components.GLDrawingControl.WndProc(Message& m) at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam) 
 File: C:\Program Files (x86)\Bentley\SewerGEMS\x64\SewerGEMS.exe InternalName: OriginalFilename: FileVersion: 10.0.0.40 FileDescription: Bentley SewerGEMS Product: Bentley SewerGEMS ProductVersion: 10.0.0.40 Debug: False Patched: False PreRelease: False PrivateBuild: False SpecialBuild: False Language: English (United States) Size: 1202168 bytes 
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