diff --git a/RuriLib/Blocks/BlockParse.cs b/RuriLib/Blocks/BlockParse.cs
index 3830e48..2184a8a 100644
--- a/RuriLib/Blocks/BlockParse.cs
+++ b/RuriLib/Blocks/BlockParse.cs
@@ -5,6 +5,7 @@ using RuriLib.LS;
 using System;
 using System.Collections.Generic;
 using System.Text.RegularExpressions;
+using System.Windows.Media;
 
 namespace RuriLib
 {
diff --git a/RuriLib/Models/Key.cs b/RuriLib/Models/Key.cs
index 51bef5a..fe2b15d 100644
--- a/RuriLib/Models/Key.cs
+++ b/RuriLib/Models/Key.cs
@@ -26,7 +26,11 @@ namespace RuriLib.Models
         /// <returns>Whether the comparison is valid</returns>
         public bool CheckKey(BotData data)
         {
-            return ConditionChecker.Verify(LeftTerm, Condition, RightTerm, data);
+            try
+            {
+                return ConditionChecker.Verify(LeftTerm, Condition, RightTerm, data);
+            }
+            catch { return false; } // Return false if e.g. we can't parse the number for a LessThan/GreaterThan comparison.
         }
     }
 }