diff --git a/Src/Utilities/AlloVarGen/AllomorphGeneratorDll/AlloGenFormBase.cs b/Src/Utilities/AlloVarGen/AllomorphGeneratorDll/AlloGenFormBase.cs
index df0ffd122c..641351f96b 100644
--- a/Src/Utilities/AlloVarGen/AllomorphGeneratorDll/AlloGenFormBase.cs
+++ b/Src/Utilities/AlloVarGen/AllomorphGeneratorDll/AlloGenFormBase.cs
@@ -1091,9 +1091,17 @@ protected virtual void lBoxOperations_SelectedIndexChanged(object sender, EventA
 				if (ActionOp.ReplaceOpRefs.Count == 0)
 				{
 					// need at least one replace action
-					Replace replace = CreateNewReplace();
-					AlloGens.AddReplaceOp(replace);
-					lBoxReplaceOps.Items.Add(replace);
+					if (AlloGens.ReplaceOperations.Count > 0)
+					{
+						ActionOp.ReplaceOpRefs.Add(AlloGens.ReplaceOperations.ElementAt(0).Guid);
+					}
+					else
+					{
+						Replace replace = CreateNewReplace();
+						AlloGens.AddReplaceOp(replace);
+						lBoxReplaceOps.Items.Add(replace);
+					}
+					MarkAsChanged(true);
 				}
 				StemName = ActionOp.StemName;
 				tbStemName.Text = StemName.Name;
@@ -1105,6 +1113,7 @@ protected virtual void lBoxOperations_SelectedIndexChanged(object sender, EventA
 		protected void RefreshReplaceListBox()
 		{
 			lBoxReplaceOps.Items.Clear();
+			List<string> brokenRefs = new List<string>();
 			foreach (string guid in ReplaceOpRefs)
 			{
 				Replace replace = AlloGens.FindReplaceOp(guid);
@@ -1112,6 +1121,15 @@ protected void RefreshReplaceListBox()
 				{
 					lBoxReplaceOps.Items.Add(replace);
 				}
+				else
+				{
+					brokenRefs.Add(guid);
+				}
+			}
+			foreach (string guid in brokenRefs)
+			{
+				ReplaceOpRefs.Remove(guid);
+				MarkAsChanged(true);
 			}
 			if (ReplaceOpRefs.Count > 0)
 				lBoxReplaceOps.SetSelected(0, true);
diff --git a/Src/Utilities/AlloVarGen/AllomorphGeneratorDll/SimpleMatchDlgAlloGen.resx b/Src/Utilities/AlloVarGen/AllomorphGeneratorDll/SimpleMatchDlgAlloGen.resx
index 74b4f19aca..9bbfd9f52f 100644
--- a/Src/Utilities/AlloVarGen/AllomorphGeneratorDll/SimpleMatchDlgAlloGen.resx
+++ b/Src/Utilities/AlloVarGen/AllomorphGeneratorDll/SimpleMatchDlgAlloGen.resx
@@ -423,7 +423,7 @@
     <value>8, 19</value>
   </data>
   <data name="$this.ClientSize" type="System.Drawing.Size, System.Drawing">
-    <value>488, 172</value>
+    <value>823, 255</value>
   </data>
   <data name="$this.Text" xml:space="preserve">
     <value>Match for forms containing...</value>