Skinning .NET forms in a ActiveX environment?

We are using own build VB.NET dll's (2008) in our older ActiveX applications (VB6) using a activex interface. The .NET dll's are running in-process in de older EXE which is based on ActiveX. The skinning in the apllication it self work fine, but the framework doesn't skin the form from the newer .NET components when they appear.
Though, it is possible to skin if the .NET form by catching the windows handle and using the command:

SkinFramework.ApplyWindow lngDotNetHandle

Now the window IS skinned, but only a few controls and the frame. Buttons for instance are not skinned. Also subforms are not skinned at all.

We have tried the following code:

SkinFramework.AddWindowClass "WindowsForms10.BUTTON.app.0.33c0d9d", "Button"

but that seems to do nothing.

Question: is there a method to skin also all VB.NET forms and components out of a ActiveX (VB6) application in case they are incorporated in the way as described above?

Thanks, but nope!
It doesn't seems to work. Maybe you have done some other setting to make it happen?

No, I didn't: I have not the slightest idea where I can find them or where to download them......