Recently we had a need to host some ActiveX controls inside a WPF window. Hosting controls in a .NET Windows Forms app is pretty straight-forward, basically register the control, add it to your toolbox in Visual Studio, then drag-n-drop the control on your form. Hosting the control in a WPF window is possible by the use of a WindowsFormsHost. Here is a walkthrough for hosting an ActiveX control in WPF from MSDN.
However we found that some of our controls gave licensing errors which crashed the application. These were our own custom controls that contained licensed third party controls. Everything seemed to work when the controls were called from a VB executable, but when hosting them in WPF, the controls crashed if the developer license wasn’t installed on the computer.