Please read some book (or at least good paper) on COM essentials. It will be difficult for you to go further without this knowledge.
Tanks a lot! I gona do this.
But I still don't know why when I create the field with success I can not reach the functions of this object.
My project is an applications project and I have one wrapper class for cortona controls and the Shelley library.
Is it enought or I need something else?
CreateObject always returns generic field interface for all field types it created. According to COM rules, you can call QueryInterface on this field interface, requesting any other interface implemented by particular field class. It will be IMFNodeObject in case of MFNode field.
CreateField()