There were many good suggestions for improvements to the Event Generator extension so I have uploaded the source FLA so that you can tweak it to suit your own needs. You can also check it out if you want to see what it takes to make a custom panel for Flash. Basically you have to call the MMExecute function and pass it a string of JSFL. Look in the Flash help files under Extending Flash for more information on what’s possible.
Once you have modified the FLA and produce a SWF file you will need to put it in a certain directory in order for Flash to see it. On the Mac it will be something like /Users/[your name]/Library/Application Support/Adobe/Flash CS3/en/Configuration/WindowSWF. For Windows it will be something like C:\Documents and Settings\All Users\Application Data\Macromedia\Flash CS3\en\Configuration\WindowSWF. Just poke around and you will find it. Just be sure to put the SWF in the WindowSWF folder and restart Flash to see the changes.
Have fun with it!