Licensing ActiveX Controls

I'm developing an application using ActiveX controls that needs a license key.
As I insert those controls using the class COleClientItem, I've encountered many problems in passing the correct license key during their creation.
I've found a solution modifying the MFC COleClientItem::CreateNewItem and using IClassFactory2, but the program fails loading a saved document, because I can't pass a valid LicenseKey before the call to ::OleSave .
Is there anyone who can help me?