Вызов C++ DLL с маршалированием на C#

Прошу помощи, т. к. столкнулся с проблемой вызова DLL (не .NET). Есть библиотека "AwUsbApi.dll" с 4-мя функциями доступными для вызова, приведу пример на одной из них "AwUsbConnect"

Ее вызов для C++

 __declspec(dllexport)
    AWUSB_STATUS
    _cdecl
    AwUsbConnect (
        IN  LPCWSTR         Hub,    
        IN  PAWUSB_STATUS   Status,
        IN  DWORD           Timeout,
        IN  HANDLE          hEvent OPTIONAL
    );

Мой вызов ее на С#:

    [DllImport("AwUsbApi.dll", EntryPoint = "AwUsbConnect", 
        CharSet = CharSet.Unicode)]
    public static extern int AwConnect(
        [MarshalAs(UnmanagedType.LPWStr)] string IP, 
        [MarshalAs(UnmanagedType.LPWStr)] StringBuilder Status, 
        int TimeOut);

Но, к сожалению, это не работает, статусы меняются, но реального воздействия на физическое устройство не происходит =(

Ниже описание функции:

• AwUsbConnect
• Parms:
• Hub
• [in] AwUsb Hub IP Address in string format. (e.g. "192.168.1.10:3" for
• host 192.168.1.10 and group 3).
• Status
• [out] Updated upon return from function, and, when hEvent is non- NULL,
• after the connect operation completes. See Return Values.
• Timeout
• [in] Specifies how long to wait for connection to succeed, in milliseconds.
• Must be non-zero. Set value to INFINITE in order to wait forever.
• Returns AWUSB_STATUS_TIMEOUT if timeout interval elapses.
• hEvent
• [in] Handle to an event which will be set to the signaled state when the
• operation has been completed. If hEvent is NULL, this function will
• block until it completes. If hEvent is non-NULL, then the function
• returns immediately, usually with AWUSB_STATUS_PENDING unless an error
• has occurred. To create an event object, use the CreateEvent function.
• An application must wait until hEvent has been signaled before calling
• CloseHandle.