🚀 Added (New Features)

• Custom Set Builder Testing Mode: The Custom Set Builder tab now functions as a live recoil testing tool. When toggled ON while the tab is active, the custom X/Y recoil values are applied instead of the selected operator's recoil, allowing real-time dial-in of recoil sets. Switching to any other tab automatically restores normal operator recoil.

📂 File-Level Changes Summary
• MainWindow.xaml: Named TabControl and added SelectionChanged handler for tab tracking.
• MainWindow.xaml.cs: Added UpdateCustomSetState() to sync custom recoil mode with RecoilEngine based on tab focus and toggle state.
• RecoilEngine.cs: Added CustomModeActive, CustomRecoilX, CustomRecoilY fields; HandleRecoilTick() checks custom mode first before falling back to mergedSets lookup.

Lithium/MainWindow.xaml

@@ -116,7 +116,7 @@
 
         <!-- Main Content -->
         <Grid Margin="0,35,0,0">
-            <TabControl Background="#1E1E1E" Foreground="White">
+            <TabControl x:Name="MainTabControl" Background="#1E1E1E" Foreground="White" SelectionChanged="MainTabControl_SelectionChanged">
                 <!-- Console Tab -->
                 <TabItem Header="Console">
                     <Grid Background="#252525" Margin="10">

Lithium/MainWindow.xaml.cs

@@ -451,7 +451,40 @@ namespace Lithium
         private void ToggleCustomSet_Click(object sender, RoutedEventArgs e)
         {
             customSetEnabled = !customSetEnabled;
-            UpdateCustomSetConsole(customSetEnabled ? "Set is ON" : "Set is OFF");
+            UpdateCustomSetState();
+        }
+
+        private void MainTabControl_SelectionChanged(object sender, SelectionChangedEventArgs e)
+        {
+            UpdateCustomSetState();
+        }
+
+        private void UpdateCustomSetState()
+        {
+            var selectedTab = MainTabControl.SelectedItem as TabItem;
+            bool onCustomTab = selectedTab != null &&
+                string.Equals(selectedTab.Header?.ToString(), "Custom Set Builder", StringComparison.OrdinalIgnoreCase);
+
+            if (customSetEnabled && onCustomTab)
+            {
+                if (double.TryParse(RecoilXTextBox.Text, System.Globalization.NumberStyles.Float,
+                    System.Globalization.CultureInfo.InvariantCulture, out double x) &&
+                    double.TryParse(RecoilYTextBox.Text, System.Globalization.NumberStyles.Float,
+                    System.Globalization.CultureInfo.InvariantCulture, out double y))
+                {
+                    RecoilEngine.CustomModeActive = true;
+                    RecoilEngine.CustomRecoilX = x;
+                    RecoilEngine.CustomRecoilY = y;
+                    UpdateCustomSetConsole($"Custom Set ACTIVE | X:{x} Y:{y}");
+                    return;
+                }
+                UpdateCustomSetConsole("Error: Invalid recoil values");
+            }
+            else
+            {
+                RecoilEngine.CustomModeActive = false;
+                UpdateCustomSetConsole(customSetEnabled ? "Set is ON (switch to tab to activate)" : "Set is OFF");
+            }
         }
 
         // AA0145

Lithium/OperatorSets.cs

@@ -405,6 +405,8 @@ namespace Lua
             isQuickSwapping = true;
             try
             {
+                string preSwitchSet = CurrentSet;
+
                 if (!ConfigLoader.betaTest)
                 {
                     if (inAttackers && !onAttackers)
@@ -444,7 +446,7 @@ namespace Lua
                 {
                     if (string.IsNullOrEmpty(originalSetBeforeQuickSwap))
                     {
-                        originalSetBeforeQuickSwap = CurrentSet;
+                        originalSetBeforeQuickSwap = preSwitchSet;
                     }
                     SetCurrentSet(targetOp);
                 }

Lithium/RecoilEngine.cs

@@ -20,6 +20,10 @@ namespace Lua
         private static double _remainderX, _remainderY;
         private static double _jitterMultiplierX, _jitterMultiplierY;
 
+        public static bool CustomModeActive = false;
+        public static double CustomRecoilX = 0;
+        public static double CustomRecoilY = 0;
+
         private static bool IsDown(int key)
         {
             return (GetAsyncKeyState(key) & 0x8000) != 0;
@@ -61,12 +65,19 @@ namespace Lua
         {
             try
             {
+                int now = Environment.TickCount;
+
+                if (CustomModeActive)
+                {
+                    HandleJitter(now);
+                    ApplyRecoil((CustomRecoilX, CustomRecoilY));
+                    return;
+                }
+
                 string setName = OperatorSets.CurrentSet;
 
                 if (!OperatorSets.mergedSets.TryGetValue(setName, out var recoil)) return;
 
-                int now = Environment.TickCount;
-
                 HandleJitter(now);
                 ApplyRecoil(recoil);
             }