You have to do two things:
- Add a target drop target listener to your graphical viewer:
getGraphicalViewer().addDropTargetListener(new TemplateTransferDropTargetListener(getGraphicalViewer()));
- Add a drag source listener listener to the palette:
getEditDomain().getPaletteViewer().addDragSourceListener( new TemplateTransferDragSourceListener(getEditDomain().getPaletteViewer()));
- change your creation tools to
CombinedTemplateCreationEntry
A more thorough explanation can be found in the blog post I created for the occasion