APPCRASH error when exiting RealDWG WinForms App

I have developed a C# winforms app with RealDWG SDK. When I close my form I get the "App has stopped working" error below.

I've added in some Dispose methods to see if that was the issue, but I still get the error.

I added a dispose method to my HostApplication class and I called my Winform dispose method.

I thought that the error was caused by unfinished RealDWG business at the Form Closing event.

I am using RealDWG 2013, Visual Studio 2010 SP1, Windows 7 64-bit.

I also have AutoCAD 2012 and 2013 installed.

I know that AutoCAD and RealDWG both use acdb19.dll.

My app contains 6 classes with around 1000 lines of code on each class, so to paste in my code would be impossible. Here is my code structure.

I start by implementing a HostApplicationService Class (MyHost.cs)

Then I call my Windows Form. (MainForm.cs)

From my form I collect object data from a SqlDatabase.

Once the data is aquired, I send the data to a Class that handles my AutoCAD classes. (AutoCAD.cs)

In this class I create my RealDWG Database.

Next I pass the database to various IDisposable classes that perform AutoCAD actions.

I.E, CreateTitleBlock() CreateLayers(), DrawShape(); etc..

Everything works great, except when I go to close the app, I get the error.

I dispose everything I can think of right before exiting.

I've tried

this.Close();

Application.Exit();

Any ideas on how to dispose the app or close it cleanly?

Thanks,

Eric

Here is the error....

Problem signature:

  Problem Event Name: APPCRASH

  Application Name: LongBayRD.exe

  Application Version: 1.0.0.0

  Application Timestamp: 519fa185

  Fault Module Name: acdb19.dll

  Fault Module Version: 19.0.55.0

Fault Module Timestamp: 4f309c70

  Exception Code: c0000005

  Exception Offset: 0000000000058166