MyExperience uses a heavily modified version of the Simkin scripting language described on our Wiki here. I've uploaded a program for Windows, called ScriptWindow, to the Wiki. ScriptWindow allows you to play around with the scripting language a bit and get used to its syntactical structure. Note that this runs in Windows (e.g., XP or Vista) and not on the device. Thus, it's a nice little sandbox with which to experiment with loops and conditions among other operations.
You can download ScriptWindow here.