InvokeMethod of Windows Workflow 4 can encounter E

Question

Thank you for reading at first.

I designed a WPF application which rehosted the Designer, Toolbox and Properties of Windows Workflow. My Idea is really simple that I just want have visualization at runtime about my workflow and design them in the runtime as well.

ISSUE:

Now I try to Invoke a Method of a class under the same namespace of whole application. The class is called MyTwsClass. Please have a look below:

It is extremely Simple. The TwsClass is from a Reference ActiveX of Interactive Brokers Trading Software. This ActiveX simply provide the method and event for you to communicate with your account. Alright, I implement the MyConnect() method as you can see and this method simply set up some string and int variables to be parameters of connect method from TwsClass. I noticed that I could not set MyTwsClass or MyConnect method as static.

Now, at runtime designer, I try to invoke the MyConnect method. First of all, picture below:

Since MyTwsClass could not be a static class with static method (I guess it is because it inherits from the ActiveX class TwsClass, I am not sure as a newbie.) So I wanna invoke the instance method. It has no complaints before running the workflow. After running this, I expect that I should be able to connect to the API of the trading software.

Now I run the workflow:

Right after clicking the running button, it runs and I got pop up window to tell me that APP has crashed with exception code C0000005. If I click the close option, my WPF application will be closed. BUT before I close it, I could see that ACTUALLY the crashed WPF actually connected to the API as you can see in picture above to tell me that 1 is connected......

I tried my best to check this problem on Internet. I am kind of have sense that it is all because of some issue within Interop or COM process between my WPF and the reference ActiveX as the crash window indicated that the TwsSocket.dll is the reason.

But I really could not figure out further.....