diff --git a/OpenGL.Net.CoreUI/NativeWindowMouseEventArgs.cs b/OpenGL.Net.CoreUI/NativeWindowMouseEventArgs.cs
index bbaa524d..df9b2adb 100644
--- a/OpenGL.Net.CoreUI/NativeWindowMouseEventArgs.cs
+++ b/OpenGL.Net.CoreUI/NativeWindowMouseEventArgs.cs
@@ -74,6 +74,7 @@ internal NativeWindowMouseEventArgs(DeviceContext deviceContext, IntPtr renderCo
 		{
 			Location = location;
 			Buttons = buttons;
+			WheelTicks = wheelTicks;
 		}
 
 		#endregion
diff --git a/OpenGL.Net.CoreUI/NativeWindowWinNT.cs b/OpenGL.Net.CoreUI/NativeWindowWinNT.cs
index c7929dfc..a9c848d5 100644
--- a/OpenGL.Net.CoreUI/NativeWindowWinNT.cs
+++ b/OpenGL.Net.CoreUI/NativeWindowWinNT.cs
@@ -243,7 +243,7 @@ private IntPtr WindowsWndProc_BUTTONDOUBLECLICK(IntPtr hWnd, IntPtr wParam, IntP
 		
 		private IntPtr WindowsWndProc_MOUSEWHEEL(IntPtr hWnd, IntPtr wParam, IntPtr lParam)
 		{
-			short wheelTicks = (short)(((wParam.ToInt32() >> 16) & 0xFFFF) / /* WHEEL_DELTA */ 120);
+			short wheelTicks = (short)(((wParam.ToInt64() >> 16) & 0xFFFF) / /* WHEEL_DELTA */ 120);
 
 			OnMouseWheel(WindowsWndProc_GetMouseLocation(lParam), WindowsWndProc_GetMouseButtons(wParam), wheelTicks);
 
@@ -263,7 +263,7 @@ private Point WindowsWndProc_GetMouseLocation(IntPtr lParam)
 		private static MouseButton WindowsWndProc_GetMouseButtons(IntPtr wParam)
 		{
 			MouseButton buttons = MouseButton.None;
-			int wParamValue = wParam.ToInt32() & 0xFFFF;
+			int wParamValue = wParam.ToInt64() & 0xFFFF;
 
 			if ((wParamValue & 0x0001) != 0)
 				buttons |= MouseButton.Left;