diff --git a/GsaGH/Components/4_Analysis/CreateModalDynamicParameter.cs b/GsaGH/Components/4_Analysis/CreateModalDynamicParameter.cs
index 975aa9e7a..9c5edfdfb 100644
--- a/GsaGH/Components/4_Analysis/CreateModalDynamicParameter.cs
+++ b/GsaGH/Components/4_Analysis/CreateModalDynamicParameter.cs
@@ -130,30 +130,15 @@ public override void SetSelected(int i, int j) {
     }
 
     private static ModeCalculationMethod GetModeStrategy(string name) {
-      IEnumerable<ModeCalculationMethod> items = _modeCalculationMethod.Where(x => x.Value.Equals(name)).Select(x => x.Key);
-      if (items.Any()) {
-        return items.First();
-      } else {
-        throw new ArgumentException("Unable to convert " + name + " to mode calculation strategy");
-      }
+      return _modeCalculationMethod.Where(x => x.Value.Equals(name)).Select(x => x.Key).First();
     }
 
     private static Direction GetDirection(string name) {
-      IEnumerable<Direction> items = _massDirection.Where(x => x.Value.Equals(name)).Select(x => x.Key);
-      if (items.Any()) {
-        return items.First();
-      } else {
-        throw new ArgumentException("Unable to convert " + name + " to direction");
-      }
+      return _massDirection.Where(x => x.Value.Equals(name)).Select(x => x.Key).First();
     }
 
     private static ModalMassOption GetMassOption(string name) {
-      IEnumerable<ModalMassOption> items = _massOptions.Where(x => x.Value.Equals(name)).Select(x => x.Key);
-      if (items.Any()) {
-        return items.First();
-      } else {
-        throw new ArgumentException("Unable to convert " + name + " to mass option");
-      }
+      return _massOptions.Where(x => x.Value.Equals(name)).Select(x => x.Key).First();
     }
 
     private void UpdateParameters(ModeCalculationMethod modeMethod) {
@@ -171,7 +156,7 @@ private void UpdateParameters(ModeCalculationMethod modeMethod) {
     }
 
     private void UnregisterParameters() {
-      for (int i = Params.Input.Count - 1; i > 0; i--) {
+      for (int i = Params.Input.Count - 1; i > -1; i--) {
         Params.UnregisterInputParameter(Params.Input[i], true);
       }
     }
diff --git a/GsaGH/Parameters/4_Analysis/ModalDynamicAnalysis.cs b/GsaGH/Parameters/4_Analysis/GsaModalDynamicAnalysis.cs
similarity index 100%
rename from GsaGH/Parameters/4_Analysis/ModalDynamicAnalysis.cs
rename to GsaGH/Parameters/4_Analysis/GsaModalDynamicAnalysis.cs
diff --git a/GsaGH/Parameters/4_Analysis/ModalDynamicAnalysisGoo.cs b/GsaGH/Parameters/4_Analysis/GsaModalDynamicAnalysisGoo.cs
similarity index 100%
rename from GsaGH/Parameters/4_Analysis/ModalDynamicAnalysisGoo.cs
rename to GsaGH/Parameters/4_Analysis/GsaModalDynamicAnalysisGoo.cs
diff --git a/GsaGH/Parameters/4_Analysis/ModalDynamicAnalysisParameter.cs b/GsaGH/Parameters/4_Analysis/GsaModalDynamicAnalysisParameter.cs
similarity index 93%
rename from GsaGH/Parameters/4_Analysis/ModalDynamicAnalysisParameter.cs
rename to GsaGH/Parameters/4_Analysis/GsaModalDynamicAnalysisParameter.cs
index ce852474c..1af64e761 100644
--- a/GsaGH/Parameters/4_Analysis/ModalDynamicAnalysisParameter.cs
+++ b/GsaGH/Parameters/4_Analysis/GsaModalDynamicAnalysisParameter.cs
@@ -32,8 +32,6 @@ protected override GsaModalDynamicGoo PreferredCast(object data) {
       switch (data) {
         case GsaAnalysisTaskGoo analysisTask:
           return new GsaModalDynamicGoo(new GsaModalDynamic(analysisTask.Value.ApiTask));
-        case GsaModalDynamicGoo dynamicAnalysis:
-          return new GsaModalDynamicGoo(dynamicAnalysis.Value);
         default:
           this.AddRuntimeError($"Data conversion failed from {data.GetTypeName()} to ModalDynamicAnalysis parameter");
           return new GsaModalDynamicGoo(null);
diff --git a/GsaGHTests/2_GooWrappers/PersistentParameters/GsaModalDynamicParameter.cs b/GsaGHTests/2_GooWrappers/PersistentParameters/GsaModalDynamicParameter.cs
new file mode 100644
index 000000000..e686eb4b3
--- /dev/null
+++ b/GsaGHTests/2_GooWrappers/PersistentParameters/GsaModalDynamicParameter.cs
@@ -0,0 +1,57 @@
+
+using System.Linq;
+
+using Grasshopper.Kernel;
+
+using GsaGH;
+using GsaGH.Parameters;
+using GsaGH.Parameters.Enums;
+
+using GsaGHTests.Components.Analysis;
+using GsaGHTests.Helpers;
+
+using OasysGH.Components;
+
+using Xunit;
+
+namespace GsaGHTests.GooWrappers {
+  [Collection("GrasshopperFixture collection")]
+  public class GsaModalDynamicParameterTests {
+
+    [Fact]
+    public void GsaModalDynamicParameterPreferredCastTest() {
+      GH_OasysComponent comp = CreateAnalysisTaskTests.CreateAnalysisTaskComponent(ModeCalculationMethod.FrquencyRange);
+      object output = ComponentTestHelper.GetOutput(comp);
+      var param = new GsaModalDynamicParameter();
+      param.AddVolatileData(new Grasshopper.Kernel.Data.GH_Path(0), 0, output);
+      Assert.NotNull(param.VolatileData.AllData(false).First());
+      Assert.Contains("FrquencyRange", ComponentTestHelper.GetOutput(param).ToString());
+    }
+
+    [Fact]
+    public void ToStringTest() {
+      GH_OasysComponent comp = CreateAnalysisTaskTests.CreateAnalysisTaskComponent(ModeCalculationMethod.FrquencyRange);
+      object output = ComponentTestHelper.GetOutput(comp);
+      var param = new GsaModalDynamicParameter();
+      param.AddVolatileData(new Grasshopper.Kernel.Data.GH_Path(0), 0, output);
+      Assert.NotNull(param.VolatileData.AllData(false).First());
+    }
+
+    [Fact]
+    public void GsaModalDynamicParameterPreferredCastErrorTest() {
+      int i = 0;
+      var param = new GsaModalDynamicParameter();
+      param.AddVolatileData(new Grasshopper.Kernel.Data.GH_Path(0), 0, i);
+      Assert.False(param.VolatileData.AllData(false).First().IsValid);
+      Assert.Single(param.RuntimeMessages(GH_RuntimeMessageLevel.Error));
+    }
+
+    [Fact]
+    public void ParameterThenPluginInfoValueShouldBeValid() {
+      GH_OasysComponent comp = CreateModalDynamicParameterByFrquencyRangeTest.ComponentMother();
+      var output = (GsaModalDynamicGoo)ComponentTestHelper.GetOutput(comp);
+      Assert.Equal(PluginInfo.Instance, output.PluginInfo);
+    }
+
+  }
+}
diff --git a/GsaGHTests/3_Components/4_Analysis/CreateModalDynamicParameterTests.cs b/GsaGHTests/3_Components/4_Analysis/CreateModalDynamicParameterTests.cs
index fb060029f..99da686e8 100644
--- a/GsaGHTests/3_Components/4_Analysis/CreateModalDynamicParameterTests.cs
+++ b/GsaGHTests/3_Components/4_Analysis/CreateModalDynamicParameterTests.cs
@@ -160,7 +160,7 @@ private void PrepareComponent(ModalMassOption massOption, Direction direction) {
       _modeCalculationStrategy = _modalDynamicAnalysis.ModeCalculationStrategy as ModeCalculationStrategyByFrequency;
     }
 
-    public static GH_OasysComponent ComponentMother(ModalMassOption massOption, Direction direction) {
+    public static GH_OasysComponent ComponentMother(ModalMassOption massOption= ModalMassOption.LumpMassAtNode, Direction direction= Direction.Y) {
       var comp = new CreateModalDynamicParameter();
       comp.CreateAttributes();
       comp.SetSelected(0, 1);