As we can't visually design a panel with controls, load it as a factory template, and create new instances of it in a such way that it could be used as "new lines" (ListItems) of a CustomListView (it would be beautiful, by the way), should be great at least to add a new feature to the Abstract Designer, a "View as Source", this way we could see the equivalent code of that design done, copy/paste, and optionally make adjustments in the code being made to create such factory code.