Registration and properties are requirements of visual designers. If they aren't registered, the visual designer can't display a list of controls available to let you pick one and couldn't initialize it if you don't introduce first the path and the ClsID, that they retrieve from the registry. Properties are used to allow you to enter individual values at design time.
Both COM servers and ActiveX controls can be used without registering them first. In the case of visual ActiveX controls, the OLE container must allow to accept a path and a ClsID instead of a ProgID.
Both COM servers and ActiveX controls can be used without registering them first. In the case of visual ActiveX controls, the OLE container must allow to accept a path and a ClsID instead of a ProgID.