it crashes when you turn the brightness too far down or the ditter too far up. as it says below, you are dividing by zero in some cases.
Exception details:
PaintDotNet.WorkerThreadException: Worker thread threw an exception ---> System.DivideByZeroException: Attempted to divide by zero.
at PaintDotNet.Effects.UserScript.Render(Surface dst, Surface src, Rectangle rect)
at PaintDotNet.Effects.UserScript.Render(EffectConfigToken parameters, RenderArgs dstArgs, RenderArgs srcArgs, Rectangle[] rois, Int32 startIndex, Int32 length)
at PaintDotNet.Effects.BackgroundEffectRenderer.RendererContext.RenderImpl()
--- End of inner exception stack trace ---
at PaintDotNet.Effects.BackgroundEffectRenderer.Join()
at PaintDotNet.Effects.BackgroundEffectRenderer.Start()
at PaintDotNet.Menus.EffectMenuBase.EffectConfigTokenChangedHandler(Object sender, EventArgs e)
at PaintDotNet.Effects.EffectConfigDialog.OnEffectTokenChanged()
at PaintDotNet.Effects.TwoAmountsConfigDialogBase.amount2Slider_ValueChanged(Object sender, EventArgs e)
at System.Windows.Forms.TrackBar.OnValueChanged(EventArgs e)
at System.Windows.Forms.TrackBar.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)