1. You need to select Runge-Kutta 4th order numerical method in the evolution page.
2. It depends on how you wrote the evolution page. Please upload your ejs xml source as attachement.

If you want to open the xml source for EJS simulation download at this  web site.
1.Double click download jar file to run it,
2. Right click and select [b]open EJS model[/b] , the EJS xml source will be loaded into EJS automatically.