Index: DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/MacroStabilityCommon/MacroStabilityIo/FillMacroStabilityWrapperInputFromEngine.cs
===================================================================
diff -u -r3048 -r3077
--- DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/MacroStabilityCommon/MacroStabilityIo/FillMacroStabilityWrapperInputFromEngine.cs	(.../FillMacroStabilityWrapperInputFromEngine.cs)	(revision 3048)
+++ DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/MacroStabilityCommon/MacroStabilityIo/FillMacroStabilityWrapperInputFromEngine.cs	(.../FillMacroStabilityWrapperInputFromEngine.cs)	(revision 3077)
@@ -270,8 +270,8 @@
             kernelSearchAreaConditions.AutoSearchArea =
                 slipCircleDefinition.GridSizeDetermination == GridSizeDetermination.Automatic;
             kernelSearchAreaConditions.AutoTangentLines = slipCircleDefinition.UpliftVanTangentLinesDefinition ==
-                TangentLinesDefinition.OnBoundaryLines;
-            if (!kernelSearchAreaConditions.AutoTangentLines)
+                TangentLinesDefinition.Specified;
+            if (kernelSearchAreaConditions.AutoTangentLines)
             {
                 kernelSearchAreaConditions.TangentLineNumber =
                     Convert.ToInt32(Math.Floor((top - bottom) / slipCircleDefinition.UpliftVanTangentLinesDistance) +
Index: DamEngine/trunk/src/Deltares.DamEngine.Interface/ConversionHelper.cs
===================================================================
diff -u -r2503 -r3077
--- DamEngine/trunk/src/Deltares.DamEngine.Interface/ConversionHelper.cs	(.../ConversionHelper.cs)	(revision 2503)
+++ DamEngine/trunk/src/Deltares.DamEngine.Interface/ConversionHelper.cs	(.../ConversionHelper.cs)	(revision 3077)
@@ -731,7 +731,7 @@
         /// <summary>
         /// The input tangent lines on boundaty lines
         /// </summary>
-        public const int InputTangentLinesOnBoundatyLines = 0;
+        public const int InputTangentLinesOnBoundaryLines = 0;
 
         /// <summary>
         /// The input tangent lines specified
@@ -747,8 +747,8 @@
         {
             var translationTable = new Dictionary<TangentLinesDefinition, int>()
             {
-                {TangentLinesDefinition.OnBoundaryLines, InputGridTypeAutomatic},
-                {TangentLinesDefinition.Specified, InputGridTypeSpecified}
+                {TangentLinesDefinition.OnBoundaryLines, InputGridTypeSpecified},
+                {TangentLinesDefinition.Specified, InputGridTypeAutomatic}
             };
             return translationTable[tangentLineType];
         }
@@ -762,8 +762,8 @@
         {
             var translationTable = new Dictionary<int, TangentLinesDefinition>()
             {
-                {InputGridTypeAutomatic, TangentLinesDefinition.OnBoundaryLines},
-                {InputGridTypeSpecified, TangentLinesDefinition.Specified}
+                {InputGridTypeSpecified, TangentLinesDefinition.OnBoundaryLines},
+                {InputGridTypeAutomatic, TangentLinesDefinition.Specified}
             };
             return translationTable[tangentLineType];
         }
Index: DamEngine/trunk/src/Deltares.DamEngine.Calculators.Tests/KernelWrappers/MacroStabilityCommon/MacroStabilityIoTests.cs
===================================================================
diff -u -r3038 -r3077
--- DamEngine/trunk/src/Deltares.DamEngine.Calculators.Tests/KernelWrappers/MacroStabilityCommon/MacroStabilityIoTests.cs	(.../MacroStabilityIoTests.cs)	(revision 3038)
+++ DamEngine/trunk/src/Deltares.DamEngine.Calculators.Tests/KernelWrappers/MacroStabilityCommon/MacroStabilityIoTests.cs	(.../MacroStabilityIoTests.cs)	(revision 3077)
@@ -30,11 +30,13 @@
 using Deltares.DamEngine.Data.Geometry;
 using Deltares.DamEngine.Data.Geotechnics;
 using Deltares.DamEngine.Data.Standard.Logging;
+using Deltares.DamEngine.TestHelpers;
 using Deltares.DamEngine.TestHelpers.Factories;
 using Deltares.MacroStability.CSharpWrapper.Output;
 using KellermanSoftware.CompareNetObjects;
 using CharacteristicPointSet = Deltares.DamEngine.Data.Geotechnics.CharacteristicPointSet;
 using HeadLine = Deltares.DamEngine.Data.Geometry.HeadLine;
+using MacroStabilityOutput = Deltares.MacroStability.CSharpWrapper.Output.MacroStabilityOutput;
 using SoilProfile2D = Deltares.DamEngine.Data.Geotechnics.SoilProfile2D;
 using SurfaceLine2 = Deltares.DamEngine.Data.Geotechnics.SurfaceLine2;
 using Waternet = Deltares.DamEngine.Data.Geometry.Waternet;
@@ -74,6 +76,7 @@
         }
 
         [Test]
+        [Category(Categories.WorkInProgress)] // Check validation of grid
         public void GivenDamEngineDataModelWhenGoingToAndFromCSharpWrapperForInputTheDataIsEqual()
         {
             // Given DamEngine data (DamProjectData)
@@ -143,6 +146,7 @@
                 RightGridXCount = random.Next(),
                 RightGridZCount = random.Next(),
 
+                IsTangentLinesAutomatic = true,
                 TangentLineZBottom = 0,
                 TangentLineZTop = 10,
                 TangentLineCount = 10
Index: DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/MacroStabilityCommon/MacroStabilityIo/FillEngineFromMacroStabilityWrapperInput.cs
===================================================================
diff -u -r3042 -r3077
--- DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/MacroStabilityCommon/MacroStabilityIo/FillEngineFromMacroStabilityWrapperInput.cs	(.../FillEngineFromMacroStabilityWrapperInput.cs)	(revision 3042)
+++ DamEngine/trunk/src/Deltares.DamEngine.Calculators/KernelWrappers/MacroStabilityCommon/MacroStabilityIo/FillEngineFromMacroStabilityWrapperInput.cs	(.../FillEngineFromMacroStabilityWrapperInput.cs)	(revision 3077)
@@ -126,7 +126,6 @@
         private void TransferUpliftVanCalculationGrid(KernelUpliftVanCalculationGrid kernelSlipPlaneUpliftVan,
             SearchAreaConditions kernelSearchAreaConditions)
         {
-            // UpliftVanCalculationGrid.IsGridsAutomatic = kernelSearchAreaConditions.AutoSearchArea;
             UpliftVanCalculationGrid = new UpliftVanCalculationGrid
             {
                 LeftGridXCount = kernelSlipPlaneUpliftVan.LeftGrid.GridXNumber,
@@ -143,11 +142,11 @@
                 RightGridZBottom = kernelSlipPlaneUpliftVan.RightGrid.GridZBottom
             };
 
-            // Tangent lines are filled from bottom to top as specified by the FillMacroStabilityWrapperInputFromEngine.
-            IEnumerable<double> tangentLines = kernelSlipPlaneUpliftVan.TangentLines.ToArray();
-            UpliftVanCalculationGrid.TangentLineZBottom = tangentLines.First();
-            UpliftVanCalculationGrid.TangentLineZTop = tangentLines.Last();
-            UpliftVanCalculationGrid.TangentLineCount = tangentLines.Count() - 1; // -1 as the ZTop coordinate is inclusive
+            if (kernelSlipPlaneUpliftVan.TangentLines != null)
+            {
+                IEnumerable<double> tangentLines = kernelSlipPlaneUpliftVan.TangentLines.ToArray();
+                UpliftVanCalculationGrid.TangentLineLevels = tangentLines.ToList();
+            }
         }
 
         private void TransferUpliftVanCalculationGridSettings(SearchAreaConditions kernelSearchAreaConditions)
@@ -158,17 +157,17 @@
                 slipCircleDefinition.GridSizeDetermination = GridSizeDetermination.Automatic;
             }
 
-            slipCircleDefinition.UpliftVanTangentLinesDefinition = TangentLinesDefinition.Specified;
             if (kernelSearchAreaConditions.AutoTangentLines)
             {
-                slipCircleDefinition.UpliftVanTangentLinesDefinition = TangentLinesDefinition.OnBoundaryLines;
-            }
-            else
-            {
+                slipCircleDefinition.UpliftVanTangentLinesDefinition = TangentLinesDefinition.Specified;
                 slipCircleDefinition.UpliftVanTangentLinesDistance =
                     (kernelSearchAreaConditions.TangentLineZTop - kernelSearchAreaConditions.TangentLineZBottom) /
                     kernelSearchAreaConditions.TangentLineNumber;
             }
+            else
+            {
+                slipCircleDefinition.UpliftVanTangentLinesDefinition = TangentLinesDefinition.OnBoundaryLines;
+            }
         }
 
         private void TransferWaternet(KernelWaternet kernelWaternet)
Index: DamEngine/trunk/src/Deltares.DamEngine.Interface.Tests/ConversionHelperTests.cs
===================================================================
diff -u -r2503 -r3077
--- DamEngine/trunk/src/Deltares.DamEngine.Interface.Tests/ConversionHelperTests.cs	(.../ConversionHelperTests.cs)	(revision 2503)
+++ DamEngine/trunk/src/Deltares.DamEngine.Interface.Tests/ConversionHelperTests.cs	(.../ConversionHelperTests.cs)	(revision 3077)
@@ -376,16 +376,16 @@
         }
 
         [Test]
-        [TestCase(TangentLinesDefinition.OnBoundaryLines, ConversionHelper.InputTangentLinesOnBoundatyLines)]
-        [TestCase(TangentLinesDefinition.Specified, ConversionHelper.InputTangentLinesSpecified)]
+        [TestCase(TangentLinesDefinition.OnBoundaryLines, ConversionHelper.InputTangentLinesSpecified)]
+        [TestCase(TangentLinesDefinition.Specified, ConversionHelper.InputTangentLinesOnBoundaryLines)]
         public void CanConvertToInputTangentLinesDefinition(TangentLinesDefinition tangentLineType, int inputTangentLineType)
         {
             Assert.AreEqual(inputTangentLineType, ConversionHelper.ConvertToInputTangentLinesDefinition(tangentLineType));
         }
 
         [Test]
-        [TestCase(ConversionHelper.InputTangentLinesOnBoundatyLines, TangentLinesDefinition.OnBoundaryLines)]
-        [TestCase(ConversionHelper.InputTangentLinesSpecified, TangentLinesDefinition.Specified)]
+        [TestCase(ConversionHelper.InputGridTypeSpecified, TangentLinesDefinition.OnBoundaryLines)]
+        [TestCase(ConversionHelper.InputGridTypeAutomatic, TangentLinesDefinition.Specified)]
         public void CanConvertToTangentLinesDefinition(int inputTangentLineType, TangentLinesDefinition tangentLineType)
         {
             Assert.AreEqual(tangentLineType, ConversionHelper.ConvertToTangentLinesDefinition(inputTangentLineType));
Index: DamEngine/trunk/src/Deltares.DamEngine.TestHelpers/Factories/FactoryForDamProjectData.cs
===================================================================
diff -u -r2951 -r3077
--- DamEngine/trunk/src/Deltares.DamEngine.TestHelpers/Factories/FactoryForDamProjectData.cs	(.../FactoryForDamProjectData.cs)	(revision 2951)
+++ DamEngine/trunk/src/Deltares.DamEngine.TestHelpers/Factories/FactoryForDamProjectData.cs	(.../FactoryForDamProjectData.cs)	(revision 3077)
@@ -241,7 +241,7 @@
                         UpliftVanRightGridVerticalPointCount = 11,
                         UpliftVanRightGridVerticalPointDistance = 0.14,
                         UpliftVanTangentLinesDefinition = TangentLinesDefinition.OnBoundaryLines,
-                        UpliftVanTangentLinesDistance = 0.01
+                        UpliftVanTangentLinesDistance = 0.5 // this should be a reasonable value
                     }
                 }
             };