My setup is as follows:
There is function written C++, that must be compiled to DLL. This DLL is linked to some CAD (computer aded design) tool, that has special interface for it.
I want to add to this function some GUI (graphical user interface). So the creation of a window is necessary.
I've tried already with Win32, but without success.
The problem is that CreateWindow function requires application instance handle, that is provided by Windows itself when window is created in "normal conditions".

Any ideas ?

Perhaps in the MFC there is some particular staff to do this ...