.NET exception at Bentley.Civil.Geometry.Model.GeometricSpaceCoordinateConverter.ConvertCoordinates

This exception was raised when I attempted to use the dynamic cross section view to establish the beginning station for a variable offset profile line.

System.NullReferenceException: Object reference not set to an instance of an object.
   at Bentley.Civil.Geometry.Model.GeometricSpaceCoordinateConverter.ConvertCoordinates(SmartPoint smartPoint, GeometricSpace targetSpace)
   at Bentley.Civil.Objects.UI.Coordinates.CoordinatesManager.ConvertSmartPointToViewCoordinates(SmartPoint smartPoint, IViewport viewport)
   at Bentley.Civil.Objects.UI.Coordinates.CoordinatesManager.DoFixPoint(IEditableButtonEvent cursorEvent)
   at Bentley.Civil.Objects.UI.Coordinates.CoordinatesManager.OnFixPoint(IEditableButtonEvent cursorEvent)
   at Bentley.Civil.CadSystem.Microstation.MstnInputManager.OnPointFilterEvent(_dPoint3d* ptP, Int32 viewIndex, Int32 eventType)
   at Bentley.Civil.CadSystem.Microstation.?A0xec45a7bb.inqmn_PointFilterFunction(_dPoint3d* ptP, Int32 viewIndex, Int32 eventType)
   at Bentley.Internal.MicroStation.CoreHook.DispatchNoHandler(UInt32* argStack, UInt32 mysp, IntPtr pFunc)
   at Bentley.Internal.MicroStation.CoreHook.Dispatch(UInt32* argStack, UInt32 mysp, IntPtr pFunc)

I clicked the button to activate the tool, then I clicked the profile from which I wanted a variable offset. When asking where it should start and what the offset should be, I simply moved my cursor into the dynamic cross section window and it immediately froze.

Using Geopak SS4 .872.

It is not reproducible, that I can tell. I tried the operation again and it seems to work fine.