Ok, in the ActionScript settings, you need to set the Library Path and Source Path. In Library Path, link to the feathers swc file and the starling swc file. They're pretty easy to find (obviously you have to have downloaded both frameworks). The flex/core stuff will be added automatically the first time you try to publish the swf.
Add the import statements so Flash can find starling. If you go to my blog (linked at the end of the presentation), you can download the example files that include the FeathersComponents class that I made.
Now we're initializing starling with the custom FeathersComponents class, starting starling, and adding an event listener for when the starling root is created (we need this in order to access our class and call methods on it).
In your callback function, first make sure you are setting the proper event type in the function parameters. We're listening for a starling event, not a flash event, so you have to spell it out for flash (if you are using flash events too then you will always have to write the full path to differentiate them).
We're going to set the starling root to a variable called gui. This is used to call functions and properties of FeathersComponents (here we're making a scrolling list and scrolling textfield).
Starling runs on the GPU and as such, its display list is actually underneath the flash display list. So if you need things to overlap and you are modifying an existing file, you will need to make everything Starling objects so they overlap properly.
Text will appear tiny when testing. It's fine on the actual device.
As mentioned earlier, starling has its own display list, movieclips, events, etc. These will clash with the Flash namespace so you have to spell things out for Flash.