I finally found out why some third-party components on a runtime-created TFrame didn't skin properly anymore after upgrading to the latest version of AC:
When you add your components to the ThirdPartyList of the sSkinManager, make sure to get all upper and lower-case letters of your component's name right. The design time editor of the sSkinManager is case sensitive! For example: entering the control class name TImageENView doesn't work, but TImageEnView does. I wasted several hours on this… 🙁
HTH