OpenSkin-Designer
Panels
Colored tree view
screen search
fold/unfold xml code
quick add buttons (add screen, panel, widget, label, pixmap; delete item)
simple autocomplete in code
toggle conditional hiding element (show all, none, random, default)
toggle markers (border indicators of elements)
position replacement to 'center' disabled
bugfixes
etc.
To-Do:
some performance improvements
parse includes
(https://raw.githubusercontent.com/iMaxxx/OpenSkin-Designer/master/Preview.png)