Some RCP-newbies are having difficulties to correctly setup their environment for RCP/Plugin development. Most of them are familiar with Eclipse but not using the Eclipse for RCP/RAP developers package. The problem is sneaky because everything is working except that you don’t get proposals when adding child to the extension. See the following video.
How to fix that? You have to install Eclipse RCP Plug-in Developer Resources from Helios repository and this video shows you how.
Now you can develop the RCP application as you like.