diff --git a/AssemblyRemapper/Remapper/Remapper.cs b/AssemblyRemapper/Remapper/Remapper.cs
index 7e0b3ff..f7e6733 100644
--- a/AssemblyRemapper/Remapper/Remapper.cs
+++ b/AssemblyRemapper/Remapper/Remapper.cs
@@ -11,6 +11,10 @@ public class Remapper
 {
     public static bool IsRunning { get; private set; } = false;
 
+    public delegate void OnCompleteHandler(object sender, EventArgs e);
+
+    public event OnCompleteHandler OnComplete;
+
     private static Stopwatch Stopwatch = new();
 
     /// <summary>
@@ -260,6 +264,7 @@ public class Remapper
 
         Reset();
         IsRunning = false;
+        OnComplete.Invoke(this, EventArgs.Empty);
     }
 
     private void Reset()
diff --git a/AssemblyRemapperGUI/Form1.cs b/AssemblyRemapperGUI/Form1.cs
index 26402dd..23c7103 100644
--- a/AssemblyRemapperGUI/Form1.cs
+++ b/AssemblyRemapperGUI/Form1.cs
@@ -15,10 +15,8 @@ namespace AssemblyRemapperGUI
             InitializeComponent();
             PopulateDomainUpDowns();
 
-            foreach (var remap in DataProvider.Remaps)
-            {
-                RemapTreeView.Nodes.Add(GUI.GenerateTreeNode(remap));
-            }
+            Remapper.OnComplete += ReloadTreeView;
+            ReloadTreeView(this, EventArgs.Empty);
         }
 
         #region BUTTONS
@@ -101,7 +99,7 @@ namespace AssemblyRemapperGUI
         {
             if (Remapper.IsRunning) { return; }
 
-            Task.Run(() => Remapper.InitializeRemap());
+            Remapper.InitializeRemap();
         }
 
         private void SaveMappingFileButton_Click(object sender, EventArgs e)
@@ -338,5 +336,20 @@ namespace AssemblyRemapperGUI
             IsDerivedUpDown.BuildStringList("IsDerived");
             HasGenericParametersUpDown.BuildStringList("HasGenericParams");
         }
+
+        /// <summary>
+        /// Subscribes the the remappers OnComplete event
+        /// </summary>
+        /// <param name="sender"></param>
+        /// <param name="e"></param>
+        private void ReloadTreeView(object sender, EventArgs e)
+        {
+            RemapTreeView.Nodes.Clear();
+
+            foreach (var remap in DataProvider.Remaps)
+            {
+                RemapTreeView.Nodes.Add(GUI.GenerateTreeNode(remap));
+            }
+        }
     }
 }
\ No newline at end of file
diff --git a/AssemblyRemapperGUI/Utils/GUI.cs b/AssemblyRemapperGUI/Utils/GUI.cs
index 53c8082..5465be7 100644
--- a/AssemblyRemapperGUI/Utils/GUI.cs
+++ b/AssemblyRemapperGUI/Utils/GUI.cs
@@ -132,7 +132,7 @@ internal static class GUI
         remapTreeItem.Nodes.Add(IsDerivedNode);
         remapTreeItem.Nodes.Add(HasGenericsNode);
 
-        if (model.SearchParams.IncludeMethods.Count > 0)
+        if (model.SearchParams.IncludeMethods?.Count > 0)
         {
             var includeMethodsNode =
                 GenerateNodeFromList(model.SearchParams.IncludeMethods, "Include Methods");
@@ -140,7 +140,7 @@ internal static class GUI
             remapTreeItem.Nodes.Add(includeMethodsNode);
         }
 
-        if (model.SearchParams.ExcludeMethods.Count > 0)
+        if (model.SearchParams.ExcludeMethods?.Count > 0)
         {
             var excludeMethodsNode =
                 GenerateNodeFromList(model.SearchParams.ExcludeMethods, "Exclude Methods");
@@ -148,7 +148,7 @@ internal static class GUI
             remapTreeItem.Nodes.Add(excludeMethodsNode);
         }
 
-        if (model.SearchParams.IncludeFields.Count > 0)
+        if (model.SearchParams.IncludeFields?.Count > 0)
         {
             var includeFieldsNode =
                 GenerateNodeFromList(model.SearchParams.IncludeFields, "Include Fields");
@@ -156,7 +156,7 @@ internal static class GUI
             remapTreeItem.Nodes.Add(includeFieldsNode);
         }
 
-        if (model.SearchParams.ExcludeFields.Count > 0)
+        if (model.SearchParams.ExcludeFields?.Count > 0)
         {
             var excludeFieldsNode =
                 GenerateNodeFromList(model.SearchParams.ExcludeFields, "Exclude Fields");
@@ -164,7 +164,7 @@ internal static class GUI
             remapTreeItem.Nodes.Add(excludeFieldsNode);
         }
 
-        if (model.SearchParams.IncludeProperties.Count > 0)
+        if (model.SearchParams.IncludeProperties?.Count > 0)
         {
             var includeProperties =
                 GenerateNodeFromList(model.SearchParams.IncludeProperties, "Include Properties");
@@ -172,7 +172,7 @@ internal static class GUI
             remapTreeItem.Nodes.Add(includeProperties);
         }
 
-        if (model.SearchParams.ExcludeProperties.Count > 0)
+        if (model.SearchParams.ExcludeProperties?.Count > 0)
         {
             var excludeProperties =
                 GenerateNodeFromList(model.SearchParams.ExcludeProperties, "Exclude Properties");
@@ -180,7 +180,7 @@ internal static class GUI
             remapTreeItem.Nodes.Add(excludeProperties);
         }
 
-        if (model.SearchParams.IncludeNestedTypes.Count > 0)
+        if (model.SearchParams.IncludeNestedTypes?.Count > 0)
         {
             var includeNestedTypes =
                 GenerateNodeFromList(model.SearchParams.IncludeNestedTypes, "Include Nested Types");
@@ -188,7 +188,7 @@ internal static class GUI
             remapTreeItem.Nodes.Add(includeNestedTypes);
         }
 
-        if (model.SearchParams.IncludeNestedTypes.Count > 0)
+        if (model.SearchParams.IncludeNestedTypes?.Count > 0)
         {
             var excludeNestedTypes =
                 GenerateNodeFromList(model.SearchParams.ExcludeNestedTypes, "Exclude Nested Types");