You should be able to copy the code to 3.47 if you open two version of EJS
Just define  the same variables, copy the same initialization/evolution/... and add similar GUI elements.
The only difference is that there is no [b]two states button[/b] in EJS 3.47
So the play/pause button need to be separate as two buttons.

And you need to adjust the code to fit with your system.

I am willing to help you do you job: I already give you an example.
And you should be able to finish it by yourself! You need to at least try it!