Here is one step by step swf file which shows you how to create kepler motion with EJS 3.4. 
(There are more function available with new EJS4, but the basic structure are the same.)

Here is another one for [url=]simple harmonic motion[/url]

There are more [url=]SWF movies show step by step instructions[/url] to create java simulation with EJS.
However the GUI shown in the SWF are in Chinese because those are developed when I taught our under-graduate students about EJS.

I will try to create more SWF files when I found available free time to d it.
Please post your questions about EJS at  [url=]Questions related to EJS[/url], I will try to help as soon as I can.
Yes. We need to users to help each others. And I hope we can form [b]EJS user community[/b] soon!