Error under Windows 7

Hi. I just started getting this error after installing WIn 7 Build 7100. It occurs when I try to change the type of files to search for to Only Props, only poses etc... If I click continue, the program seems to work right for a bit then starts doing it more often and becomes totally unstable and eventually crashes. Here is the erro info on it.

************** Exception Text **************
System.NullReferenceException: Object reference not set to an instance of an object.
at Advanced_Library.MyImagesContainer.filter()
at Advanced_Library.MyImagesContainer.AddExtension(String extension, Int32 position, Boolean update)
at Advanced_Library.MyImageList.AddExtension(String ext, Boolean update)
at Advanced_Library.Form1.ExecuteFileTypeChanges()
at Advanced_Library.Form1.FileTypeOnly_Click(Object sender, EventArgs e)
at Advanced_Library.Form1.FileType_MouseUp(Object sender, MouseEventArgs e)
at System.Windows.Forms.ToolStripItem.HandleMouseUp(MouseEventArgs e)
at System.Windows.Forms.ToolStrip.OnMouseUp(MouseEventArgs mea)
at System.Windows.Forms.ToolStripDropDown.OnMouseUp(MouseEventArgs mea)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ToolStrip.WndProc(Message& m)
at System.Windows.Forms.ToolStripDropDown.WndProc(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)

************** Loaded Assemblies **************
mscorlib
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.4918 (NetFXspW7.050727-4900)
CodeBase: file:///C:/Windows/Microsoft.NET/Framework64/v2.0.50727/mscorlib.dll
----------------------------------------
Advanced_Library
Assembly Version: 1.9.1.11
Win32 Version: 1.9.1.11
CodeBase: file:///C:/Users/Rich/Desktop/Advanced%20Library%20for%20Poser/Advanced_Library_1_9_1_11/Advanced_Library.exe
----------------------------------------
System
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.4918 (NetFXspW7.050727-4900)
CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System/2.0.0.0__b77a5c561934e089/System.dll
----------------------------------------
System.Windows.Forms
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.4918 (NetFXspW7.050727-4900)
CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.Windows.Forms/2.0.0.0__b77a5c561934e089/System.Windows.Forms.dll
----------------------------------------
System.Drawing
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.4918 (NetFXspW7.050727-4900)
CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.Drawing/2.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll
----------------------------------------
System.Configuration
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.4918 (NetFXspW7.050727-4900)
CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.Configuration/2.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll
----------------------------------------
System.Xml
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.4918 (NetFXspW7.050727-4900)
CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.Xml/2.0.0.0__b77a5c561934e089/System.Xml.dll
----------------------------------------
Interop.Shell32
Assembly Version: 1.0.0.0
Win32 Version: 1.0.0.0
CodeBase: file:///C:/Users/Rich/Desktop/Advanced%20Library%20for%20Poser/Advanced_Library_1_9_1_11/Interop.Shell32.DLL
----------------------------------------
System.DirectoryServices
Assembly Version: 2.0.0.0
Win32 Version: 2.0.50727.4918 (NetFXspW7.050727-4900)
CodeBase: file:///C:/Windows/assembly/GAC_MSIL/System.DirectoryServices/2.0.0.0__b03f5f7f11d50a3a/System.DirectoryServices.dll
----------------------------------------

Is anyone else getting this error?