The Examples folder accompanying MacStim contains several simple resources and some scripts ready to go. If you double click the scripts from within the folder (after copying it to your hard disk), then MacStim will open them up ready to run (though you may need to customize the file-opening options in the Preferences… dialog box)
Note the order of the fields, and values for each of the time fields and experiment. Most experiments with pictures and sounds should be able to be scripted in similar ways.
